@effect/platform-bun@4.0.0

Patch Changes

• #8598 988c467 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 2c552f2 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.

  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, 5a81a6f, 68b6394, 5250ca6, 5f9c9d1, 3278821, 83429b4, 0af6d0c, 927e01e, 10d8524, 35ac25a, 29e0aa7, 8783536, df77fff, ef7d77f, 035e369, f72790c, aa19472, 988c467, 735b77b, e5f7d12, 2c552f2]:

  • effect@4.0.0
  • @effect/platform-node-shared@4.0.0