From 1f4749a64591a6829d5659ab9bf5199dae48dacb Mon Sep 17 00:00:00 2001
From: effect-bot <129879685+effect-bot@users.noreply.github.com>
Date: Wed, 30 Sep 2026 20:21:15 +0200
Subject: [PATCH] Version Packages

---
 .../concrete-schema-brand-identifiers.md      |   5 -
 .changeset/fix-atom-family-finalizer-race.md  |   5 -
 .../fix-cluster-workflow-stale-resume.md      |   5 -
 .../fix-concurrent-atom-sync-results.md       |   5 -
 .../fix-mutable-hash-map-key-retention.md     |   5 -
 .../fix-queue-partial-batch-starvation.md     |   5 -
 .changeset/fix-race-loser-left-running.md     |   5 -
 .changeset/fix-rpc-interrupt-fiber-id-null.md |   5 -
 .changeset/fix-schema-brand-union-codegen.md  |   5 -
 .../fix-schema-encoding-checks-projection.md  |   5 -
 .changeset/partition-success-first.md         |   5 -
 .changeset/pre.json                           |   4 -
 .changeset/pre/effect-4-0.md                  |  98 ----------------
 .changeset/quiet-layers-preserve-errors.md    |   5 -
 .changeset/rpc-missed-pong.md                 |   5 -
 .changeset/rpc-union-tag-inference.md         |   5 -
 .changeset/schema-brand-type-only.md          |   5 -
 .../schema-jit-checked-encoding-sources.md    |   5 -
 .../schema-projection-reference-sharing.md    |   5 -
 .changeset/schema-union-candidate-parsers.md  |   5 -
 .changeset/server-websocket-exit-codes.md     |   7 --
 .changeset/test-schema-effect-variants.md     |   5 -
 .changeset/workflow-reset-retry.md            |   5 -
 packages/ai/anthropic/CHANGELOG.md            |  71 +++++++++++
 packages/ai/anthropic/package.json            |   2 +-
 packages/ai/openai-compat/CHANGELOG.md        |  71 +++++++++++
 packages/ai/openai-compat/package.json        |   2 +-
 packages/ai/openai/CHANGELOG.md               |  71 +++++++++++
 packages/ai/openai/package.json               |   2 +-
 packages/ai/openrouter/CHANGELOG.md           |  71 +++++++++++
 packages/ai/openrouter/package.json           |   2 +-
 packages/ai/typesafe/CHANGELOG.md             |  71 +++++++++++
 packages/ai/typesafe/package.json             |   2 +-
 packages/atom/react/CHANGELOG.md              |  71 +++++++++++
 packages/atom/react/package.json              |   2 +-
 packages/atom/solid/CHANGELOG.md              |  71 +++++++++++
 packages/atom/solid/package.json              |   2 +-
 packages/atom/vue/CHANGELOG.md                |  71 +++++++++++
 packages/atom/vue/package.json                |   2 +-
 packages/effect/CHANGELOG.md                  | 111 ++++++++++++++++++
 packages/effect/package.json                  |   2 +-
 packages/opentelemetry/CHANGELOG.md           |  71 +++++++++++
 packages/opentelemetry/package.json           |   2 +-
 packages/platform/browser/CHANGELOG.md        |  71 +++++++++++
 packages/platform/browser/package.json        |   2 +-
 packages/platform/bun/CHANGELOG.md            |  74 ++++++++++++
 packages/platform/bun/package.json            |   2 +-
 packages/platform/deno/CHANGELOG.md           |  72 ++++++++++++
 packages/platform/deno/package.json           |   2 +-
 packages/platform/node-shared/CHANGELOG.md    |  71 +++++++++++
 packages/platform/node-shared/package.json    |   2 +-
 packages/platform/node/CHANGELOG.md           |  74 ++++++++++++
 packages/platform/node/package.json           |   2 +-
 packages/sql/clickhouse/CHANGELOG.md          |  72 ++++++++++++
 packages/sql/clickhouse/package.json          |   2 +-
 packages/sql/d1/CHANGELOG.md                  |  71 +++++++++++
 packages/sql/d1/package.json                  |   2 +-
 packages/sql/libsql/CHANGELOG.md              |  71 +++++++++++
 packages/sql/libsql/package.json              |   2 +-
 packages/sql/mssql/CHANGELOG.md               |  71 +++++++++++
 packages/sql/mssql/package.json               |   2 +-
 packages/sql/mysql2/CHANGELOG.md              |  71 +++++++++++
 packages/sql/mysql2/package.json              |   2 +-
 packages/sql/pg/CHANGELOG.md                  |  71 +++++++++++
 packages/sql/pg/package.json                  |   2 +-
 packages/sql/pglite/CHANGELOG.md              |  71 +++++++++++
 packages/sql/pglite/package.json              |   2 +-
 packages/sql/sqlite-bun/CHANGELOG.md          |  71 +++++++++++
 packages/sql/sqlite-bun/package.json          |   2 +-
 packages/sql/sqlite-do/CHANGELOG.md           |  71 +++++++++++
 packages/sql/sqlite-do/package.json           |   2 +-
 packages/sql/sqlite-node/CHANGELOG.md         |  71 +++++++++++
 packages/sql/sqlite-node/package.json         |   2 +-
 packages/sql/sqlite-react-native/CHANGELOG.md |  71 +++++++++++
 packages/sql/sqlite-react-native/package.json |   2 +-
 packages/sql/sqlite-wasm/CHANGELOG.md         |  71 +++++++++++
 packages/sql/sqlite-wasm/package.json         |   2 +-
 packages/tools/docgen/CHANGELOG.md            |  72 ++++++++++++
 packages/tools/docgen/package.json            |   2 +-
 packages/tools/doctest/CHANGELOG.md           |  71 +++++++++++
 packages/tools/doctest/package.json           |   2 +-
 packages/tools/openapi-generator/CHANGELOG.md |  72 ++++++++++++
 packages/tools/openapi-generator/package.json |   2 +-
 packages/vitest/CHANGELOG.md                  |  71 +++++++++++
 packages/vitest/package.json                  |   2 +-
 85 files changed, 2282 insertions(+), 240 deletions(-)
 delete mode 100644 .changeset/concrete-schema-brand-identifiers.md
 delete mode 100644 .changeset/fix-atom-family-finalizer-race.md
 delete mode 100644 .changeset/fix-cluster-workflow-stale-resume.md
 delete mode 100644 .changeset/fix-concurrent-atom-sync-results.md
 delete mode 100644 .changeset/fix-mutable-hash-map-key-retention.md
 delete mode 100644 .changeset/fix-queue-partial-batch-starvation.md
 delete mode 100644 .changeset/fix-race-loser-left-running.md
 delete mode 100644 .changeset/fix-rpc-interrupt-fiber-id-null.md
 delete mode 100644 .changeset/fix-schema-brand-union-codegen.md
 delete mode 100644 .changeset/fix-schema-encoding-checks-projection.md
 delete mode 100644 .changeset/partition-success-first.md
 delete mode 100644 .changeset/pre.json
 delete mode 100644 .changeset/pre/effect-4-0.md
 delete mode 100644 .changeset/quiet-layers-preserve-errors.md
 delete mode 100644 .changeset/rpc-missed-pong.md
 delete mode 100644 .changeset/rpc-union-tag-inference.md
 delete mode 100644 .changeset/schema-brand-type-only.md
 delete mode 100644 .changeset/schema-jit-checked-encoding-sources.md
 delete mode 100644 .changeset/schema-projection-reference-sharing.md
 delete mode 100644 .changeset/schema-union-candidate-parsers.md
 delete mode 100644 .changeset/server-websocket-exit-codes.md
 delete mode 100644 .changeset/test-schema-effect-variants.md
 delete mode 100644 .changeset/workflow-reset-retry.md

diff --git a/.changeset/concrete-schema-brand-identifiers.md b/.changeset/concrete-schema-brand-identifiers.md
deleted file mode 100644
index 51b166f9efa..00000000000
--- a/.changeset/concrete-schema-brand-identifiers.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Restrict `Schema.brand` to a single concrete identifier and require `Schema.fromBrand` to use the constructor's sole brand key. Apply `brand` or `fromBrand` repeatedly when composing distinct brands. For enum brand keys, pass the enum member instead of its string value.
diff --git a/.changeset/fix-atom-family-finalizer-race.md b/.changeset/fix-atom-family-finalizer-race.md
deleted file mode 100644
index a329120fecc..00000000000
--- a/.changeset/fix-atom-family-finalizer-race.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Prevent a stale `Atom.family` finalizer from evicting a newer cached atom.
diff --git a/.changeset/fix-cluster-workflow-stale-resume.md b/.changeset/fix-cluster-workflow-stale-resume.md
deleted file mode 100644
index 48d97a4b6af..00000000000
--- a/.changeset/fix-cluster-workflow-stale-resume.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Prevent stale concurrent workflow resumes from clearing a newer completed reply. Custom message storage implementations must honor the optional expected reply ID on `clearReplies` to provide this safety guarantee.
diff --git a/.changeset/fix-concurrent-atom-sync-results.md b/.changeset/fix-concurrent-atom-sync-results.md
deleted file mode 100644
index ccced1b8a72..00000000000
--- a/.changeset/fix-concurrent-atom-sync-results.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fix lost synchronous successes and failures in concurrent `Atom.fn` calls.
diff --git a/.changeset/fix-mutable-hash-map-key-retention.md b/.changeset/fix-mutable-hash-map-key-retention.md
deleted file mode 100644
index 8ac31dbeb16..00000000000
--- a/.changeset/fix-mutable-hash-map-key-retention.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fix `MutableHashMap` retaining previously used equal object keys after they are replaced or removed, including when `Cache` and `ScopedCache` refresh entries on hits.
diff --git a/.changeset/fix-queue-partial-batch-starvation.md b/.changeset/fix-queue-partial-batch-starvation.md
deleted file mode 100644
index f00bac6c723..00000000000
--- a/.changeset/fix-queue-partial-batch-starvation.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Keep `Queue.takeN` suspended when only part of its requested batch is available. Previously a single offer woke the batch taker in a synchronous retry loop that starved the host. `Queue.State.takers` now holds `Queue.Taker` entries: call `entry.resume(...)` instead of calling the entry as a function.
diff --git a/.changeset/fix-race-loser-left-running.md b/.changeset/fix-race-loser-left-running.md
deleted file mode 100644
index adada29ea7b..00000000000
--- a/.changeset/fix-race-loser-left-running.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Interrupt losers in `Effect.race`, `Effect.raceFirst`, `Effect.raceAll` and `Effect.raceAllFirst` when the race settles or is interrupted while other effects are still starting.
diff --git a/.changeset/fix-rpc-interrupt-fiber-id-null.md b/.changeset/fix-rpc-interrupt-fiber-id-null.md
deleted file mode 100644
index ef24546f402..00000000000
--- a/.changeset/fix-rpc-interrupt-fiber-id-null.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-The `RpcMessage.ExitEncoded` interrupt `fiberId` type now admits the `null` emitted by JSON encoding. Consumers reading encoded interrupts should handle `null` alongside `undefined`.
diff --git a/.changeset/fix-schema-brand-union-codegen.md b/.changeset/fix-schema-brand-union-codegen.md
deleted file mode 100644
index 90c97b00fa5..00000000000
--- a/.changeset/fix-schema-brand-union-codegen.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fix `SchemaRepresentation.toCodeDocument` to preserve the grouping of branded union types in generated TypeScript code.
diff --git a/.changeset/fix-schema-encoding-checks-projection.md b/.changeset/fix-schema-encoding-checks-projection.md
deleted file mode 100644
index 64bc073257b..00000000000
--- a/.changeset/fix-schema-encoding-checks-projection.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fix `Schema.toType` and `Schema.toEncoded` losing parent checks when projecting checked children without transformations. Suspended children remain opaque, and structural checks continue to be preserved.
diff --git a/.changeset/partition-success-first.md b/.changeset/partition-success-first.md
deleted file mode 100644
index 891db542774..00000000000
--- a/.changeset/partition-success-first.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-`Array`, `Chunk`, `Effect`, and `Record` `partition`, their `separate` helpers, and `Option.partitionMap` now return successes before failures, matching `Stream.partition`. Swap the tuple when moving from the previous `[failures, successes]` order.
diff --git a/.changeset/pre.json b/.changeset/pre.json
deleted file mode 100644
index 3616d3a6ea5..00000000000
--- a/.changeset/pre.json
+++ /dev/null
@@ -1,4 +0,0 @@
-{
-  "mode": "exit",
-  "tag": "rc"
-}
diff --git a/.changeset/pre/effect-4-0.md b/.changeset/pre/effect-4-0.md
deleted file mode 100644
index 82dd83c3337..00000000000
--- a/.changeset/pre/effect-4-0.md
+++ /dev/null
@@ -1,98 +0,0 @@
----
-"effect": patch
-"@effect/ai-anthropic": patch
-"@effect/ai-openai": patch
-"@effect/ai-typesafe": patch
-"@effect/ai-openai-compat": patch
-"@effect/ai-openrouter": patch
-"@effect/atom-react": patch
-"@effect/atom-solid": patch
-"@effect/atom-vue": patch
-"@effect/docgen": patch
-"@effect/doctest": patch
-"@effect/openapi-generator": patch
-"@effect/opentelemetry": patch
-"@effect/platform-browser": patch
-"@effect/platform-bun": patch
-"@effect/platform-deno": patch
-"@effect/platform-node": patch
-"@effect/platform-node-shared": patch
-"@effect/sql-clickhouse": patch
-"@effect/sql-d1": patch
-"@effect/sql-libsql": patch
-"@effect/sql-mssql": patch
-"@effect/sql-mysql2": patch
-"@effect/sql-pg": patch
-"@effect/sql-pglite": patch
-"@effect/sql-sqlite-bun": patch
-"@effect/sql-sqlite-do": patch
-"@effect/sql-sqlite-node": patch
-"@effect/sql-sqlite-react-native": patch
-"@effect/sql-sqlite-wasm": patch
-"@effect/vitest": patch
----
-
-Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
-
-**Packaging and versioning**
-
-- All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
-- `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
-- Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
-- APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
-- `effect` has no runtime dependencies.
-- New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
-
-**Core**
-
-- The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
-- Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
-- Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
-- `Clock` separates wall-clock time from monotonic time.
-- New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
-
-**Schema**
-
-- Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
-- `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
-- `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
-- Optional JIT and AOT schema compilers are available as experimental modules.
-
-**Platform, HTTP and RPC**
-
-- `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
-- The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
-- `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
-- RPC serialization is schema-aware and supports server-originated requests and notifications.
-- `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
-
-**Cluster and Workflow**
-
-- Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
-- Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
-
-**SQL**
-
-- `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
-- `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
-- `SqlError` exposes structured reasons such as `UniqueViolation`.
-
-**AI**
-
-- `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
-- The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
-- Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
-
-**CLI, Atom, observability and testing**
-
-- `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
-- `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
-- The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
-- `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
-
-**Requirements**
-
-- TypeScript 5.9 or newer. TypeScript 7 is recommended.
-- `@effect/vitest` and `@effect/doctest` require Vitest 5.
-- `@effect/atom-react` requires React 19.
-- `@effect/platform-deno` requires Deno 2.8.3 or newer.
diff --git a/.changeset/quiet-layers-preserve-errors.md b/.changeset/quiet-layers-preserve-errors.md
deleted file mode 100644
index 08d77974132..00000000000
--- a/.changeset/quiet-layers-preserve-errors.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Preserve sibling and callback cleanup failures alongside interruption in concurrent `Effect.forEach` / `Effect.all`, including shared `Layer.build`.
diff --git a/.changeset/rpc-missed-pong.md b/.changeset/rpc-missed-pong.md
deleted file mode 100644
index f4bc4f34cab..00000000000
--- a/.changeset/rpc-missed-pong.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fail in-flight RPC calls when a socket misses a pong, even with transient connection retries enabled. Missed pongs no longer invoke `onTransientError`; connection-open failures still do.
diff --git a/.changeset/rpc-union-tag-inference.md b/.changeset/rpc-union-tag-inference.md
deleted file mode 100644
index e40f04e54d4..00000000000
--- a/.changeset/rpc-union-tag-inference.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fix union-of-tag inference for flat RPC clients and `AtomRpc.query` and `AtomRpc.mutation`. Payloads and results now reflect the selected RPCs instead of resolving to `never`.
diff --git a/.changeset/schema-brand-type-only.md b/.changeset/schema-brand-type-only.md
deleted file mode 100644
index 868598010bb..00000000000
--- a/.changeset/schema-brand-type-only.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Make `Schema.brand` type-only: brand identifiers are no longer stored in AST annotations or preserved by `SchemaRepresentation`. Reapply `Schema.brand` after rebuilding a representation when a branded TypeScript type is required; checks added by `Schema.fromBrand` remain preserved. Preserve the order of equal-priority union members that share an AST when deriving JSON and string-tree codecs.
diff --git a/.changeset/schema-jit-checked-encoding-sources.md b/.changeset/schema-jit-checked-encoding-sources.md
deleted file mode 100644
index 1898cea1394..00000000000
--- a/.changeset/schema-jit-checked-encoding-sources.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Speed up JIT and AOT Schema decoding of transformations whose source has checks, such as a pattern-checked string decoded to a number. Fix compiled TemplateLiteral validation to enforce oneOf parts and preserve interpreter diagnostics when templates appear in transformation chains.
diff --git a/.changeset/schema-projection-reference-sharing.md b/.changeset/schema-projection-reference-sharing.md
deleted file mode 100644
index 757a2c05c86..00000000000
--- a/.changeset/schema-projection-reference-sharing.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Fix duplicate references in decoded and encoded schema representations when reusing schemas through optional or mutable keys.
diff --git a/.changeset/schema-union-candidate-parsers.md b/.changeset/schema-union-candidate-parsers.md
deleted file mode 100644
index c1111d80d1c..00000000000
--- a/.changeset/schema-union-candidate-parsers.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Resolve a Schema union's candidate parsers once per union instead of on every decode, so union decoding and encoding allocate less and run faster.
diff --git a/.changeset/server-websocket-exit-codes.md b/.changeset/server-websocket-exit-codes.md
deleted file mode 100644
index 9bd3d3484de..00000000000
--- a/.changeset/server-websocket-exit-codes.md
+++ /dev/null
@@ -1,7 +0,0 @@
----
-"effect": patch
-"@effect/platform-bun": patch
-"@effect/platform-node": patch
----
-
-Close server WebSockets with 1000 on success, 1001 on interruption, or 1011 on failure, while preserving explicit close codes. HTTP request scopes retain the handler's failure exit through response handling and middleware.
diff --git a/.changeset/test-schema-effect-variants.md b/.changeset/test-schema-effect-variants.md
deleted file mode 100644
index c495d4497d9..00000000000
--- a/.changeset/test-schema-effect-variants.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Add `succeedEffect`, `failEffect`, and `verifyRoundTripEffect` to `TestSchema` so assertions can use the calling Effect's services, test clock, and interruption, and mark the module and its public APIs as unstable. Preserve defects and interruption when they occur alongside schema validation failures. Rename `verifyLosslessTransformation` to `verifyRoundTrip`; existing callers must update to the new name.
diff --git a/.changeset/workflow-reset-retry.md b/.changeset/workflow-reset-retry.md
deleted file mode 100644
index f22ebe73d0a..00000000000
--- a/.changeset/workflow-reset-retry.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-"effect": patch
----
-
-Retry failed workflow run resets instead of acknowledging deferred completion before the run resumes.
diff --git a/packages/ai/anthropic/CHANGELOG.md b/packages/ai/anthropic/CHANGELOG.md
index 025d68a600b..ddf48575a22 100644
--- a/packages/ai/anthropic/CHANGELOG.md
+++ b/packages/ai/anthropic/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/ai-anthropic
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/ai/anthropic/package.json b/packages/ai/anthropic/package.json
index 11e6263b3b4..af34eba6c48 100644
--- a/packages/ai/anthropic/package.json
+++ b/packages/ai/anthropic/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/ai-anthropic",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "An Anthropic provider integration for Effect AI SDK",
diff --git a/packages/ai/openai-compat/CHANGELOG.md b/packages/ai/openai-compat/CHANGELOG.md
index 620e0b3c2db..716a0ef6b26 100644
--- a/packages/ai/openai-compat/CHANGELOG.md
+++ b/packages/ai/openai-compat/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/ai-openai-compat
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/ai/openai-compat/package.json b/packages/ai/openai-compat/package.json
index 785f807a850..2c3fac74af8 100644
--- a/packages/ai/openai-compat/package.json
+++ b/packages/ai/openai-compat/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/ai-openai-compat",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "An OpenAI compat integration for Effect",
diff --git a/packages/ai/openai/CHANGELOG.md b/packages/ai/openai/CHANGELOG.md
index 2e5097375c9..83d7e6618be 100644
--- a/packages/ai/openai/CHANGELOG.md
+++ b/packages/ai/openai/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/ai-openai
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/ai/openai/package.json b/packages/ai/openai/package.json
index 714c88d05e8..63202ff94e5 100644
--- a/packages/ai/openai/package.json
+++ b/packages/ai/openai/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/ai-openai",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "An OpenAI provider integration for Effect AI SDK",
diff --git a/packages/ai/openrouter/CHANGELOG.md b/packages/ai/openrouter/CHANGELOG.md
index 1a83126fc3a..e512e150039 100644
--- a/packages/ai/openrouter/CHANGELOG.md
+++ b/packages/ai/openrouter/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/ai-openrouter
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/ai/openrouter/package.json b/packages/ai/openrouter/package.json
index 1085b957433..6b407bb5a31 100644
--- a/packages/ai/openrouter/package.json
+++ b/packages/ai/openrouter/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/ai-openrouter",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "An OpenRouter provider integration for Effect AI SDK",
diff --git a/packages/ai/typesafe/CHANGELOG.md b/packages/ai/typesafe/CHANGELOG.md
index 5108c202944..bbfea7c9809 100644
--- a/packages/ai/typesafe/CHANGELOG.md
+++ b/packages/ai/typesafe/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/ai-typesafe
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/ai/typesafe/package.json b/packages/ai/typesafe/package.json
index ed09e8e1008..566f585b8f1 100644
--- a/packages/ai/typesafe/package.json
+++ b/packages/ai/typesafe/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/ai-typesafe",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A TypeSafe DecisionModel provider for Effect",
diff --git a/packages/atom/react/CHANGELOG.md b/packages/atom/react/CHANGELOG.md
index 86ece352c18..8db542a470d 100644
--- a/packages/atom/react/CHANGELOG.md
+++ b/packages/atom/react/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/atom-react
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/atom/react/package.json b/packages/atom/react/package.json
index ab0c70b610f..33ccd8d035f 100644
--- a/packages/atom/react/package.json
+++ b/packages/atom/react/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/atom-react",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "React bindings for the Effect Atom modules",
diff --git a/packages/atom/solid/CHANGELOG.md b/packages/atom/solid/CHANGELOG.md
index 63dceefde3f..dbe714db3b8 100644
--- a/packages/atom/solid/CHANGELOG.md
+++ b/packages/atom/solid/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/atom-solid
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/atom/solid/package.json b/packages/atom/solid/package.json
index 24cf86eeb13..0bc5b19e1a1 100644
--- a/packages/atom/solid/package.json
+++ b/packages/atom/solid/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/atom-solid",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "SolidJS bindings for the Effect Atom modules",
diff --git a/packages/atom/vue/CHANGELOG.md b/packages/atom/vue/CHANGELOG.md
index 9a13d4d0e9b..100ce4646cd 100644
--- a/packages/atom/vue/CHANGELOG.md
+++ b/packages/atom/vue/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/atom-vue
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/atom/vue/package.json b/packages/atom/vue/package.json
index d640a7d52af..3a68907c8f3 100644
--- a/packages/atom/vue/package.json
+++ b/packages/atom/vue/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/atom-vue",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "Vue bindings for the Effect Atom modules",
diff --git a/packages/effect/CHANGELOG.md b/packages/effect/CHANGELOG.md
index 9a7c3d15fc1..dd7faa1f6e0 100644
--- a/packages/effect/CHANGELOG.md
+++ b/packages/effect/CHANGELOG.md
@@ -1,5 +1,116 @@
 # effect
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8580](https://github.com/Effect-TS/effect/pull/8580) [`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d) Thanks @gcanti! - Restrict `Schema.brand` to a single concrete identifier and require `Schema.fromBrand` to use the constructor's sole brand key. Apply `brand` or `fromBrand` repeatedly when composing distinct brands. For enum brand keys, pass the enum member instead of its string value.
+
+- [#8601](https://github.com/Effect-TS/effect/pull/8601) [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af) Thanks @RizgarOzan! - Prevent a stale `Atom.family` finalizer from evicting a newer cached atom.
+
+- [#8576](https://github.com/Effect-TS/effect/pull/8576) [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3) Thanks @tim-smart! - Prevent stale concurrent workflow resumes from clearing a newer completed reply. Custom message storage implementations must honor the optional expected reply ID on `clearReplies` to provide this safety guarantee.
+
+- [#8589](https://github.com/Effect-TS/effect/pull/8589) [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e) Thanks @marek-hanzal! - Fix lost synchronous successes and failures in concurrent `Atom.fn` calls.
+
+- [#8625](https://github.com/Effect-TS/effect/pull/8625) [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd) Thanks @tim-smart! - Fix `MutableHashMap` retaining previously used equal object keys after they are replaced or removed, including when `Cache` and `ScopedCache` refresh entries on hits.
+
+- [#8619](https://github.com/Effect-TS/effect/pull/8619) [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34) Thanks @tim-smart! - Keep `Queue.takeN` suspended when only part of its requested batch is available. Previously a single offer woke the batch taker in a synchronous retry loop that starved the host. `Queue.State.takers` now holds `Queue.Taker` entries: call `entry.resume(...)` instead of calling the entry as a function.
+
+- [#8607](https://github.com/Effect-TS/effect/pull/8607) [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade) Thanks @mannyc2! - Interrupt losers in `Effect.race`, `Effect.raceFirst`, `Effect.raceAll` and `Effect.raceAllFirst` when the race settles or is interrupted while other effects are still starting.
+
+- [#8626](https://github.com/Effect-TS/effect/pull/8626) [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac) Thanks @tim-smart! - The `RpcMessage.ExitEncoded` interrupt `fiberId` type now admits the `null` emitted by JSON encoding. Consumers reading encoded interrupts should handle `null` alongside `undefined`.
+
+- [#8614](https://github.com/Effect-TS/effect/pull/8614) [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1) Thanks @gcanti! - Fix `SchemaRepresentation.toCodeDocument` to preserve the grouping of branded union types in generated TypeScript code.
+
+- [#8617](https://github.com/Effect-TS/effect/pull/8617) [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178) Thanks @gcanti! - Fix `Schema.toType` and `Schema.toEncoded` losing parent checks when projecting checked children without transformations. Suspended children remain opaque, and structural checks continue to be preserved.
+
+- [#8583](https://github.com/Effect-TS/effect/pull/8583) [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25) Thanks @KhraksMamtsov! - `Array`, `Chunk`, `Effect`, and `Record` `partition`, their `separate` helpers, and `Option.partitionMap` now return successes before failures, matching `Stream.partition`. Swap the tuple when moving from the previous `[failures, successes]` order.
+
+- [#8585](https://github.com/Effect-TS/effect/pull/8585) [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e) Thanks @roninjin10! - Preserve sibling and callback cleanup failures alongside interruption in concurrent `Effect.forEach` / `Effect.all`, including shared `Layer.build`.
+
+- [#8593](https://github.com/Effect-TS/effect/pull/8593) [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d) Thanks @tim-smart! - Fail in-flight RPC calls when a socket misses a pong, even with transient connection retries enabled. Missed pongs no longer invoke `onTransientError`; connection-open failures still do.
+
+- [#8579](https://github.com/Effect-TS/effect/pull/8579) [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1) Thanks @jasonkuhrt! - Fix union-of-tag inference for flat RPC clients and `AtomRpc.query` and `AtomRpc.mutation`. Payloads and results now reflect the selected RPCs instead of resolving to `never`.
+
+- [#8628](https://github.com/Effect-TS/effect/pull/8628) [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36) Thanks @gcanti! - Make `Schema.brand` type-only: brand identifiers are no longer stored in AST annotations or preserved by `SchemaRepresentation`. Reapply `Schema.brand` after rebuilding a representation when a branded TypeScript type is required; checks added by `Schema.fromBrand` remain preserved. Preserve the order of equal-priority union members that share an AST when deriving JSON and string-tree codecs.
+
+- [#8597](https://github.com/Effect-TS/effect/pull/8597) [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7) Thanks @Ceereals! - Speed up JIT and AOT Schema decoding of transformations whose source has checks, such as a pattern-checked string decoded to a number. Fix compiled TemplateLiteral validation to enforce oneOf parts and preserve interpreter diagnostics when templates appear in transformation chains.
+
+- [#8630](https://github.com/Effect-TS/effect/pull/8630) [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56) Thanks @gcanti! - Fix duplicate references in decoded and encoded schema representations when reusing schemas through optional or mutable keys.
+
+- [#8555](https://github.com/Effect-TS/effect/pull/8555) [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c) Thanks @front-depiction! - Resolve a Schema union's candidate parsers once per union instead of on every decode, so union decoding and encoding allocate less and run faster.
+
+- [#8598](https://github.com/Effect-TS/effect/pull/8598) [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac) Thanks @tim-smart! - Close server WebSockets with 1000 on success, 1001 on interruption, or 1011 on failure, while preserving explicit close codes. HTTP request scopes retain the handler's failure exit through response handling and middleware.
+
+- [#8632](https://github.com/Effect-TS/effect/pull/8632) [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a) Thanks @gcanti! - Add `succeedEffect`, `failEffect`, and `verifyRoundTripEffect` to `TestSchema` so assertions can use the calling Effect's services, test clock, and interruption, and mark the module and its public APIs as unstable. Preserve defects and interruption when they occur alongside schema validation failures. Rename `verifyLosslessTransformation` to `verifyRoundTrip`; existing callers must update to the new name.
+
+- [#8575](https://github.com/Effect-TS/effect/pull/8575) [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd) Thanks @tim-smart! - Retry failed workflow run resets instead of acknowledging deferred completion before the run resumes.
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/effect/package.json b/packages/effect/package.json
index 239424ec7f2..6534bb19918 100644
--- a/packages/effect/package.json
+++ b/packages/effect/package.json
@@ -1,7 +1,7 @@
 {
   "name": "effect",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "The missing standard library for TypeScript, for writing production-grade software.",
   "homepage": "https://effect.website",
diff --git a/packages/opentelemetry/CHANGELOG.md b/packages/opentelemetry/CHANGELOG.md
index 4f79d964862..fcc9bf3a68c 100644
--- a/packages/opentelemetry/CHANGELOG.md
+++ b/packages/opentelemetry/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/opentelemetry
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/opentelemetry/package.json b/packages/opentelemetry/package.json
index 186968601b5..c9b62918599 100644
--- a/packages/opentelemetry/package.json
+++ b/packages/opentelemetry/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/opentelemetry",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "OpenTelemetry integration for Effect",
   "homepage": "https://effect.website",
diff --git a/packages/platform/browser/CHANGELOG.md b/packages/platform/browser/CHANGELOG.md
index c2f90a6b8e3..cdd1fda8c8d 100644
--- a/packages/platform/browser/CHANGELOG.md
+++ b/packages/platform/browser/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/platform-browser
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/platform/browser/package.json b/packages/platform/browser/package.json
index 37f850bdbed..2f621ef0adc 100644
--- a/packages/platform/browser/package.json
+++ b/packages/platform/browser/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/platform-browser",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "Platform specific implementations for the browser",
   "homepage": "https://effect.website",
diff --git a/packages/platform/bun/CHANGELOG.md b/packages/platform/bun/CHANGELOG.md
index cb2d6d04afe..637ece3e4ab 100644
--- a/packages/platform/bun/CHANGELOG.md
+++ b/packages/platform/bun/CHANGELOG.md
@@ -1,5 +1,79 @@
 # @effect/platform-bun
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8598](https://github.com/Effect-TS/effect/pull/8598) [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac) Thanks @tim-smart! - Close server WebSockets with 1000 on success, 1001 on interruption, or 1011 on failure, while preserving explicit close codes. HTTP request scopes retain the handler's failure exit through response handling and middleware.
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+  - @effect/platform-node-shared@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/platform/bun/package.json b/packages/platform/bun/package.json
index 1ca78250719..01d101a2b68 100644
--- a/packages/platform/bun/package.json
+++ b/packages/platform/bun/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/platform-bun",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "Platform specific implementations for the Bun runtime",
   "homepage": "https://effect.website",
diff --git a/packages/platform/deno/CHANGELOG.md b/packages/platform/deno/CHANGELOG.md
index 8bbfe35ae2e..869e0344005 100644
--- a/packages/platform/deno/CHANGELOG.md
+++ b/packages/platform/deno/CHANGELOG.md
@@ -1,5 +1,77 @@
 # @effect/platform-deno
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+  - @effect/platform-node-shared@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/platform/deno/package.json b/packages/platform/deno/package.json
index d5615ae6a9a..9f002b92214 100644
--- a/packages/platform/deno/package.json
+++ b/packages/platform/deno/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/platform-deno",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "Platform specific implementations for the Deno runtime",
   "homepage": "https://effect.website",
diff --git a/packages/platform/node-shared/CHANGELOG.md b/packages/platform/node-shared/CHANGELOG.md
index 1f3e638d796..367b17a99a9 100644
--- a/packages/platform/node-shared/CHANGELOG.md
+++ b/packages/platform/node-shared/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/platform-node-shared
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/platform/node-shared/package.json b/packages/platform/node-shared/package.json
index 8284f1385b3..c7d1d54d99e 100644
--- a/packages/platform/node-shared/package.json
+++ b/packages/platform/node-shared/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/platform-node-shared",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "Unified interfaces for common platform-specific services",
   "homepage": "https://effect.website",
diff --git a/packages/platform/node/CHANGELOG.md b/packages/platform/node/CHANGELOG.md
index 55650e4ba85..4def94b7b4a 100644
--- a/packages/platform/node/CHANGELOG.md
+++ b/packages/platform/node/CHANGELOG.md
@@ -1,5 +1,79 @@
 # @effect/platform-node
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8598](https://github.com/Effect-TS/effect/pull/8598) [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac) Thanks @tim-smart! - Close server WebSockets with 1000 on success, 1001 on interruption, or 1011 on failure, while preserving explicit close codes. HTTP request scopes retain the handler's failure exit through response handling and middleware.
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+  - @effect/platform-node-shared@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/platform/node/package.json b/packages/platform/node/package.json
index 58e75367b9c..e6ed6c639cd 100644
--- a/packages/platform/node/package.json
+++ b/packages/platform/node/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/platform-node",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "Platform specific implementations for the Node.js runtime",
   "homepage": "https://effect.website",
diff --git a/packages/sql/clickhouse/CHANGELOG.md b/packages/sql/clickhouse/CHANGELOG.md
index 9b820d62853..b5dd4a09dea 100644
--- a/packages/sql/clickhouse/CHANGELOG.md
+++ b/packages/sql/clickhouse/CHANGELOG.md
@@ -1,5 +1,77 @@
 # @effect/sql-clickhouse
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+  - @effect/platform-node@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/clickhouse/package.json b/packages/sql/clickhouse/package.json
index 538a02c1f8e..1b2e4be2ea2 100644
--- a/packages/sql/clickhouse/package.json
+++ b/packages/sql/clickhouse/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-clickhouse",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A Clickhouse toolkit for Effect",
diff --git a/packages/sql/d1/CHANGELOG.md b/packages/sql/d1/CHANGELOG.md
index c5b01c979e3..a969b817181 100644
--- a/packages/sql/d1/CHANGELOG.md
+++ b/packages/sql/d1/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-d1
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/d1/package.json b/packages/sql/d1/package.json
index 7af2dba5f99..b6491526bd7 100644
--- a/packages/sql/d1/package.json
+++ b/packages/sql/d1/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-d1",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A Cloudflare D1 integration for Effect",
diff --git a/packages/sql/libsql/CHANGELOG.md b/packages/sql/libsql/CHANGELOG.md
index 07ac9ebfc51..af227b55b7a 100644
--- a/packages/sql/libsql/CHANGELOG.md
+++ b/packages/sql/libsql/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-libsql
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/libsql/package.json b/packages/sql/libsql/package.json
index 75de4ec6adf..9127c65370f 100644
--- a/packages/sql/libsql/package.json
+++ b/packages/sql/libsql/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-libsql",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A libSQL toolkit for Effect",
diff --git a/packages/sql/mssql/CHANGELOG.md b/packages/sql/mssql/CHANGELOG.md
index cf7bfb6b8c4..69250d374b7 100644
--- a/packages/sql/mssql/CHANGELOG.md
+++ b/packages/sql/mssql/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-mssql
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/mssql/package.json b/packages/sql/mssql/package.json
index d89aeab78e6..1d8cdb8eae0 100644
--- a/packages/sql/mssql/package.json
+++ b/packages/sql/mssql/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-mssql",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A Microsoft SQL Server toolkit for Effect",
diff --git a/packages/sql/mysql2/CHANGELOG.md b/packages/sql/mysql2/CHANGELOG.md
index 2493621b6b0..0c57e3c7310 100644
--- a/packages/sql/mysql2/CHANGELOG.md
+++ b/packages/sql/mysql2/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-mysql2
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/mysql2/package.json b/packages/sql/mysql2/package.json
index 4e7d9f5c7a3..95ae8b46744 100644
--- a/packages/sql/mysql2/package.json
+++ b/packages/sql/mysql2/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-mysql2",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A MySQL toolkit for Effect",
diff --git a/packages/sql/pg/CHANGELOG.md b/packages/sql/pg/CHANGELOG.md
index 15b78f84448..d2a1a594f7c 100644
--- a/packages/sql/pg/CHANGELOG.md
+++ b/packages/sql/pg/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-pg
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/pg/package.json b/packages/sql/pg/package.json
index 2cf9e3d9786..449e8f67e04 100644
--- a/packages/sql/pg/package.json
+++ b/packages/sql/pg/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-pg",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A PostgreSQL toolkit for Effect",
diff --git a/packages/sql/pglite/CHANGELOG.md b/packages/sql/pglite/CHANGELOG.md
index b0e3ccd9880..053566736c5 100644
--- a/packages/sql/pglite/CHANGELOG.md
+++ b/packages/sql/pglite/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-pglite
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/pglite/package.json b/packages/sql/pglite/package.json
index 0533992621d..59e3e011e0e 100644
--- a/packages/sql/pglite/package.json
+++ b/packages/sql/pglite/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-pglite",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A PGlite toolkit for Effect",
diff --git a/packages/sql/sqlite-bun/CHANGELOG.md b/packages/sql/sqlite-bun/CHANGELOG.md
index 4884e8b0118..129efdb2d30 100644
--- a/packages/sql/sqlite-bun/CHANGELOG.md
+++ b/packages/sql/sqlite-bun/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-sqlite-bun
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/sqlite-bun/package.json b/packages/sql/sqlite-bun/package.json
index 6b4143ca1f2..c31cf8f27d3 100644
--- a/packages/sql/sqlite-bun/package.json
+++ b/packages/sql/sqlite-bun/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-sqlite-bun",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A SQLite toolkit for Effect",
diff --git a/packages/sql/sqlite-do/CHANGELOG.md b/packages/sql/sqlite-do/CHANGELOG.md
index 1203827aa60..ba136f6602a 100644
--- a/packages/sql/sqlite-do/CHANGELOG.md
+++ b/packages/sql/sqlite-do/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-sqlite-do
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/sqlite-do/package.json b/packages/sql/sqlite-do/package.json
index 20b40d1f402..c2617b84017 100644
--- a/packages/sql/sqlite-do/package.json
+++ b/packages/sql/sqlite-do/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-sqlite-do",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A SQLite toolkit for Effect",
diff --git a/packages/sql/sqlite-node/CHANGELOG.md b/packages/sql/sqlite-node/CHANGELOG.md
index 3ed7a26d7f6..96473164df4 100644
--- a/packages/sql/sqlite-node/CHANGELOG.md
+++ b/packages/sql/sqlite-node/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-sqlite-node
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/sqlite-node/package.json b/packages/sql/sqlite-node/package.json
index 2505e12abcf..7c41bc5159c 100644
--- a/packages/sql/sqlite-node/package.json
+++ b/packages/sql/sqlite-node/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-sqlite-node",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A SQLite toolkit for Effect",
diff --git a/packages/sql/sqlite-react-native/CHANGELOG.md b/packages/sql/sqlite-react-native/CHANGELOG.md
index b9758dd2bb2..7682ed40cd4 100644
--- a/packages/sql/sqlite-react-native/CHANGELOG.md
+++ b/packages/sql/sqlite-react-native/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-sqlite-react-native
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/sqlite-react-native/package.json b/packages/sql/sqlite-react-native/package.json
index 231bee3d904..ec92d21af1b 100644
--- a/packages/sql/sqlite-react-native/package.json
+++ b/packages/sql/sqlite-react-native/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-sqlite-react-native",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A SQLite toolkit for Effect",
diff --git a/packages/sql/sqlite-wasm/CHANGELOG.md b/packages/sql/sqlite-wasm/CHANGELOG.md
index 99ee6e70c26..9dda9389777 100644
--- a/packages/sql/sqlite-wasm/CHANGELOG.md
+++ b/packages/sql/sqlite-wasm/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/sql-sqlite-wasm
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/sql/sqlite-wasm/package.json b/packages/sql/sqlite-wasm/package.json
index a4565725e61..3f4db9e2c36 100644
--- a/packages/sql/sqlite-wasm/package.json
+++ b/packages/sql/sqlite-wasm/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/sql-sqlite-wasm",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A SQLite toolkit for Effect",
diff --git a/packages/tools/docgen/CHANGELOG.md b/packages/tools/docgen/CHANGELOG.md
index 7034b6c1b4f..2de38fe28a1 100644
--- a/packages/tools/docgen/CHANGELOG.md
+++ b/packages/tools/docgen/CHANGELOG.md
@@ -1,5 +1,77 @@
 # @effect/docgen
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+  - @effect/platform-node@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/tools/docgen/package.json b/packages/tools/docgen/package.json
index fb6cd6f9675..f7bd6b01ae8 100644
--- a/packages/tools/docgen/package.json
+++ b/packages/tools/docgen/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/docgen",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "An opinionated documentation generator for Effect projects",
diff --git a/packages/tools/doctest/CHANGELOG.md b/packages/tools/doctest/CHANGELOG.md
index 29a8d6811e4..29a4f69e8f7 100644
--- a/packages/tools/doctest/CHANGELOG.md
+++ b/packages/tools/doctest/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/doctest
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/tools/doctest/package.json b/packages/tools/doctest/package.json
index f57a9c6001c..b7aed0cb371 100644
--- a/packages/tools/doctest/package.json
+++ b/packages/tools/doctest/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/doctest",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "Runs TypeScript documentation examples as Vitest tests",
diff --git a/packages/tools/openapi-generator/CHANGELOG.md b/packages/tools/openapi-generator/CHANGELOG.md
index a5315c46d08..ed3cb4f7fe6 100644
--- a/packages/tools/openapi-generator/CHANGELOG.md
+++ b/packages/tools/openapi-generator/CHANGELOG.md
@@ -1,5 +1,77 @@
 # @effect/openapi-generator
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+  - @effect/platform-node@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/tools/openapi-generator/package.json b/packages/tools/openapi-generator/package.json
index 29f75fc9c18..235c5d1140c 100644
--- a/packages/tools/openapi-generator/package.json
+++ b/packages/tools/openapi-generator/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@effect/openapi-generator",
   "type": "module",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "license": "MIT",
   "description": "Generate Effect Schema types, HTTP clients, and HttpApi modules from OpenAPI specifications",
   "homepage": "https://effect.website",
diff --git a/packages/vitest/CHANGELOG.md b/packages/vitest/CHANGELOG.md
index d89fb429822..010107dba42 100644
--- a/packages/vitest/CHANGELOG.md
+++ b/packages/vitest/CHANGELOG.md
@@ -1,5 +1,76 @@
 # @effect/vitest
 
+## 4.0.0
+
+### Patch Changes
+
+- [#8633](https://github.com/Effect-TS/effect/pull/8633) [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4) Thanks @IMax153! - Effect 4.0 is the first stable release of Effect v4. It replaces the 4.0.0 beta and release-candidate series, whose per-release notes remain below under the `4.0.0-beta.*` and `4.0.0-rc.*` headings. To upgrade from Effect 3, follow the [migration guide](https://github.com/Effect-TS/effect/blob/main/MIGRATION.md).
+  
+  **Packaging and versioning**
+  
+  - All Effect packages share one version number and are released together. Use the same version of `effect` and every `@effect/*` package.
+  - `@effect/platform`, `@effect/rpc`, `@effect/cluster`, `@effect/cli`, `@effect/ai`, `@effect/sql`, `@effect/workflow`, `@effect/experimental` and similar packages are merged into `effect`. Separate packages remain only for platforms (`@effect/platform-*`), SQL drivers (`@effect/sql-*`), AI providers (`@effect/ai-*`), framework bindings (`@effect/atom-*`), OpenTelemetry, Vitest and tooling.
+  - Modules such as `effect/http`, `effect/http-api`, `effect/rpc`, `effect/cluster`, `effect/workflow`, `effect/ai`, `effect/cli`, `effect/sql` and `effect/schema` import from `effect/<area>`. APIs tagged `@stability unstable` may have breaking changes in minor releases. APIs without a stability tag follow semver.
+  - APIs that expose a third-party dependency are tagged `@stability unstable`, because that dependency's releases can change them. This covers `NodeRedis`, `DenoRedis`, `BunRedis`, `@effect/platform-node/Undici` and the undici dispatcher APIs, the `ws` options and re-exports in the platform packages, driver-specific options and clients in `@effect/sql-clickhouse`, `@effect/sql-d1`, `@effect/sql-libsql`, `@effect/sql-mssql`, `@effect/sql-mysql2`, `@effect/sql-pglite` and `@effect/sql-sqlite-do`, the provider clients, models and generated schemas in the `@effect/ai-*` packages, `@effect/opentelemetry`, and the `vitest` re-export in `@effect/vitest`.
+  - `effect` has no runtime dependencies.
+  - New packages in v4: `@effect/platform-deno`, `@effect/sql-pglite`, `@effect/ai-openai-compat`, `@effect/ai-typesafe`, `@effect/atom-react`, `@effect/atom-solid`, `@effect/atom-vue`, `@effect/openapi-generator` and `@effect/doctest`. `@effect/docgen` now lives in this repository.
+  
+  **Core**
+  
+  - The fiber runtime was rewritten for lower memory use and faster execution, with smaller bundles and better tree-shaking.
+  - Services are defined with `Context.Service`, `FiberRef` is replaced by `Context.Reference`, `Cause` has a flat structure, and many combinators were renamed. See the migration guide for the full list.
+  - Software transactional memory is built into `Effect.tx`, with `TxRef`, `TxQueue`, `TxHashMap`, `TxPubSub`, `TxSemaphore` and related `Tx*` data types.
+  - `Clock` separates wall-clock time from monotonic time.
+  - New modules include `Semaphore`, `Latch`, `LayerRef`, `ErrorReporter`, `ByteSize`, `Newtype` and `Crypto`. `Arbitrary` is now a native property-based testing module and no longer depends on fast-check.
+  
+  **Schema**
+  
+  - Schema v4 is a new implementation with faster parsing, class-based schemas, `make` constructors on every schema, and effectful decoding with services.
+  - `SchemaRepresentation` powers JSON Schema (Draft-04, Draft-07, 2020-12 and OpenAPI 3.0/3.1) import and export, TypeScript code generation, and AI structured output.
+  - `SchemaBinary` provides a compact binary codec and is the default wire format for cluster transports.
+  - Optional JIT and AOT schema compilers are available as experimental modules.
+  
+  **Platform, HTTP and RPC**
+  
+  - `HttpApi` supports typed response headers, streaming and SSE responses, the HTTP `QUERY` method, `HttpApiTest` for in-memory testing, and much faster type checking for large APIs.
+  - The HTTP modules add static file serving, response compression, rate-limited clients and graceful server shutdown.
+  - `Socket` has a pull-based reader with backpressure and STARTTLS support. Network addresses are modeled by `effect/net`.
+  - RPC serialization is schema-aware and supports server-originated requests and notifications.
+  - `@effect/platform-deno` adds full Deno support. The Node, Bun, Deno and browser packages all provide the platform `Crypto` service, and the browser package adds IndexedDB support.
+  
+  **Cluster and Workflow**
+  
+  - Workflows can be declared with class syntax, and `DurableQueue` and an in-memory `WorkflowEngine` are available.
+  - Runner memory can be bounded with `ShardingConfig` limits. Shutdown, entity movement and persisted replies are more reliable.
+  
+  **SQL**
+  
+  - `@effect/sql-pg` uses a built-in PostgreSQL client with pipelining, prepared statements and binary codecs, and no longer depends on `pg`.
+  - `@effect/sql-sqlite-node` uses Node's built-in `node:sqlite` and requires Node 22.16 or newer.
+  - `SqlError` exposes structured reasons such as `UniqueViolation`.
+  
+  **AI**
+  
+  - `effect/ai` adds `EmbeddingModel`, the `DecisionModel` classification and rating API, dynamic tools and tool approvals.
+  - The MCP server supports protocol versions 2024-11-05 through 2026-07-28, including elicitation, sampling with tools, resource subscriptions and typed tool output.
+  - Provider packages cover Anthropic, OpenAI, OpenAI-compatible APIs and OpenRouter.
+  
+  **CLI, Atom, observability and testing**
+  
+  - `effect/cli` adds global flags, command aliases and examples, an interactive wizard mode, and shell completions for Bash, Zsh and Fish.
+  - `effect/reactivity` and the `@effect/atom-*` bindings add SSR hydration, stale-while-revalidate atoms and serializable RPC and HttpApi queries.
+  - The OTLP exporters can be configured with standard OpenTelemetry environment variables, and `@effect/opentelemetry` aligns logs and spans with the OpenTelemetry specification.
+  - `@effect/vitest` runs property tests with the native `Arbitrary` module and supports Vitest fixtures.
+  
+  **Requirements**
+  
+  - TypeScript 5.9 or newer. TypeScript 7 is recommended.
+  - `@effect/vitest` and `@effect/doctest` require Vitest 5.
+  - `@effect/atom-react` requires React 19.
+  - `@effect/platform-deno` requires Deno 2.8.3 or newer.
+- Updated dependencies [[`cbfc7b4`](https://github.com/Effect-TS/effect/commit/cbfc7b422046111c439a69ecbce7fc4f4899789d), [`5a81a6f`](https://github.com/Effect-TS/effect/commit/5a81a6f47521123a4075c6c221fb888d109778af), [`68b6394`](https://github.com/Effect-TS/effect/commit/68b639473ff211b654b49b7b82183cafd225f4a3), [`5250ca6`](https://github.com/Effect-TS/effect/commit/5250ca63c6f15152b4cdd36ef78b32ab06a0075e), [`5f9c9d1`](https://github.com/Effect-TS/effect/commit/5f9c9d17c1a2d18e3217b251d28de0015bba02fd), [`3278821`](https://github.com/Effect-TS/effect/commit/3278821a6490f7f76b30217115e921e1d3dc7f34), [`83429b4`](https://github.com/Effect-TS/effect/commit/83429b42023e79c29137381dc210a57bc0137ade), [`0af6d0c`](https://github.com/Effect-TS/effect/commit/0af6d0c8ceaf08656f76bba41e5965bbf9a76bac), [`927e01e`](https://github.com/Effect-TS/effect/commit/927e01e00579c14d446e15e077775e973d75f9a1), [`10d8524`](https://github.com/Effect-TS/effect/commit/10d8524dc40fd06075f6a70f88d3a0cbd3477178), [`35ac25a`](https://github.com/Effect-TS/effect/commit/35ac25a80bec4977a082af57a618d6a02bb41e25), [`29e0aa7`](https://github.com/Effect-TS/effect/commit/29e0aa7dcc7735e207a687ba0f6a7ddebfe0996e), [`8783536`](https://github.com/Effect-TS/effect/commit/878353689f69b555ad64f9dc14d4c66fd547360d), [`df77fff`](https://github.com/Effect-TS/effect/commit/df77fff9396fe31de72d1947ecb5b74f8cee89e1), [`ef7d77f`](https://github.com/Effect-TS/effect/commit/ef7d77f382dcb2a4f7648211ed6d674984a47c36), [`035e369`](https://github.com/Effect-TS/effect/commit/035e369b3a30bcd840a7a78ccfb94d251bf931b7), [`f72790c`](https://github.com/Effect-TS/effect/commit/f72790c618260bdfbf7a4e14d10abc2341d21e56), [`aa19472`](https://github.com/Effect-TS/effect/commit/aa1947284cee5cec68d08df9c5b41fae8fe1aa8c), [`988c467`](https://github.com/Effect-TS/effect/commit/988c467afa90449b1d441c2db645eaec236763ac), [`735b77b`](https://github.com/Effect-TS/effect/commit/735b77b65ca909ca6e41915f0d1366531c32142a), [`e5f7d12`](https://github.com/Effect-TS/effect/commit/e5f7d12af9abef188f7dc39b0207af1801b03ffd), [`2c552f2`](https://github.com/Effect-TS/effect/commit/2c552f220e09dd63d4a777db6cd20b9a13e732f4)]:
+  - effect@4.0.0
+
 ## 4.0.0-rc.118
 
 ### Patch Changes
diff --git a/packages/vitest/package.json b/packages/vitest/package.json
index 663ee84d026..0d117fbbe24 100644
--- a/packages/vitest/package.json
+++ b/packages/vitest/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@effect/vitest",
-  "version": "4.0.0-rc.118",
+  "version": "4.0.0",
   "type": "module",
   "license": "MIT",
   "description": "A set of helpers for testing Effects with vitest",