Effect is a TypeScript framework for building robust, production-ready applications using a functional effect system with a standard library. It provides primitives for side effects, type-safe concurrency and error-handling, and includes ecosystem packages for CLI tooling, observability (OpenTelemetry), distributed computing, workflows, and multiple SQL integrations.
Project status
- Effect-TS/effect appears actively maintained in late 2026, with an upstream push on 2026-09-16 and multiple package updates posted within days (notably on 2026-09-11 and 2026-09-15).
- The apparent updates cadence is fast, roughly every few days during this period, and many of the dependency bumps land as release-candidate synchronized updates (for example, effect and related packages tracking @effect/4.0.0-rc.115).
AI summary generated
Recent updates
@effect/sql-sqlite-react-native@4.0.0-rc.116
This release (@effect/sql-sqlite-react-native@4.0.0-rc.116) is described as a dependency-only update. It bumps the upstream Effect core dependency to effect@4.0.0-rc.116, and the release notes do not mention any SQL package API changes, bug fixes, or security updates. When upgrading, review the corresponding Effect changes in rc.116 for any behavioral impact.
@effect/vitest@4.0.0-rc.116
This release is labeled as a patch update for @effect/vitest, but the notes provide no Vitest-specific feature, fix, or behavioral changes. The only concrete information is that the package updated its dependency on effect to version 4.0.0-rc.116.
@effect/sql-sqlite-wasm@4.0.0-rc.116
This release is a patch-level version of @effect/sql-sqlite-wasm@4.0.0-rc.116 with no explicit functional changes called out in the release notes. The only documented change is an update to the underlying Effect dependency version.
@effect/sql-sqlite-node@4.0.0-rc.116
This release is a patch release for @effect/sql-sqlite-node@4.0.0-rc.116. The release notes only mention a dependency update to effect@4.0.0-rc.116, with no other behavioral or API changes documented.
@effect/sql-sqlite-do@4.0.0-rc.116
This @effect/sql-sqlite-do@4.0.0-rc.116 release improves Durable Object transaction behavior by adding support for nested transactions with independent child rollback. It also changes transaction scheduling and error propagation to prevent Durable Object deadlocks and to surface native transaction completion failures consistently as SqlError.
Features@effect/sql-sqlite-bun@4.0.0-rc.116
This release of @effect/sql-sqlite-bun@4.0.0-rc.116 contains only a dependency update, with no other behavior changes described in the release notes. The package updates its core dependency to effect@4.0.0-rc.116.
@effect/sql-pglite@4.0.0-rc.116
This is a patch release of @effect/sql-pglite that appears to consist primarily of an internal dependency bump. The release notes only mention an update to the Effect dependency, without listing any direct API, behavior, or bug fix changes.
@effect/sql-pg@4.0.0-rc.116
This release improves PostgreSQL connectivity and type handling in @effect/sql-pg, including smarter SSL negotiation, richer connection startup configuration, and better support for LISTEN retry behavior. It also introduces breaking codec changes for timestamp/timestamptz decoding and how unregistered OIDs are decoded, which may require application-side codec registrations or type annotation updates.
BreakingFeatures@effect/sql-mysql2@4.0.0-rc.116
This @effect/sql-mysql2 release is a patch-only update focused on refreshing several dependencies to their latest versions. Release notes do not mention any new features, bug fixes, or breaking API changes.
@effect/sql-mssql@4.0.0-rc.116
Version @effect/sql-mssql@4.0.0-rc.116 is a patch release with no user-visible changes called out in the release notes. The primary (and only) stated change is an update of dependencies, specifically to effect@4.0.0-rc.116.
effect@4.0.0-rc.116
This release adds experimental Schema JIT and AOT compilers, plus several new AI, HTTP, and utility capabilities (including Crypto ULID generation and MCP enhancements). It also includes a substantial set of breaking API changes around SchemaGetter and SchemaTransformation, and several HTTP, Stream, workflow, and file response bug fixes. Plan for TypeScript and runtime behavior updates, especially for Schema-related combinators and stricter YAML parsing.
BreakingFeatures@effect/cli@0.77.2
Release @effect/cli@0.77.2 is described as a patch that updates the TOML dependency to remove a vulnerability notice. However, the provided code diff contains many substantive changes across @effect/cli, @effect/cluster, and @effect itself, which are not mentioned in the release notes.
@effect/vitest@4.0.0-rc.115
This release is labeled as a patch/dependency bump for @effect/vitest, but the actual diff includes substantial behavioral changes in the core @effect packages that @effect/vitest depends on. The biggest functional change is in HTTP response handling, where response bodies are now omitted for status codes 204, 205, and 304, and raw streams are actively cancelled when omitted.
BreakingSecurity@effect/sql-sqlite-wasm@4.0.0-rc.115
Release @effect/sql-sqlite-wasm@4.0.0-rc.115 notes only that dependencies were updated, pointing to effect@4.0.0-rc.115. However, the diff for this release includes multiple behavioral and API-surface changes inside the effect HTTP, schema, and persistence code that are not described in the provided release notes.
@effect/sql-sqlite-react-native@4.0.0-rc.115
Release @effect/sql-sqlite-react-native@4.0.0-rc.115 is presented as a patch that only updates dependencies to effect@4.0.0-rc.115. The actual diff includes multiple behavioral changes in effect, including HTTP response body omission logic, SQL persistence query parameterization, and internal schema memoization and validation changes.
@effect/sql-sqlite-node@4.0.0-rc.115
The @effect/sql-sqlite-node@4.0.0-rc.115 release notes only state that dependencies were updated, specifically pulling in effect@4.0.0-rc.115. The code diff for this release, however, shows multiple behavioral and API-surface changes inside the effect package that will affect users transitively.
BreakingSecurityeffect@4.0.0-rc.115
effect@4.0.0-rc.115 is a patch release focused on schema initialization performance, safer HTTP response conversions, and more robust SQL persistence lookups. It also introduces several internal refactors around schema AST caching and validation and adds new test coverage for the HTTP and schema behavior.
@effect/vitest@4.0.0-rc.114
This release of @effect/vitest@4.0.0-rc.114 is a dependency update only. The release notes do not describe any direct Vitest API changes, new capabilities, or behavior fixes beyond updating the underlying effect dependency.
@effect/sql-sqlite-wasm@4.0.0-rc.114
This patch release updates the package's dependency on Effect-TS to version @effect/4.0.0-rc.114. Release notes do not mention any direct behavior changes, new APIs, or bug/security fixes within @effect/sql-sqlite-wasm itself.
@effect/sql-sqlite-react-native@4.0.0-rc.114
This release does not list any direct code changes or user-facing feature additions in the release notes. It appears to be a release-candidate synchronization that updates the underlying Effect dependency to effect@4.0.0-rc.114.