SWC (Speedy Web Compiler) is a Rust-based TypeScript and JavaScript compiler. It provides parsing and compilation capabilities, with documentation covering Rust usage (notably via the ecma parser) and JavaScript/Node installation, and it aims to make web development faster.
Project status
- Active maintenance: Yes, the GitHub source shows very recent upstream activity (last push 2026-08-19) and there are tagged updates within days of today (v1.16.1 on 2026-08-19), indicating ongoing work rather than maintenance mode.
- Apparent cadence: Roughly weekly to biweekly stable tags (1.15.43 on 2026-06-22, 1.15.46 on 2026-07-19, 1.15.47 on 2026-07-29, 1.16.0 on 2026-08-14, 1.16.1 on 2026-08-19), with frequent nightly updates in between.
AI summary generated
Recent updates
v1.16.1
v1.16.1 does not include any publisher release notes, but the code diff shows several targeted bug fixes across the SWC minifier, SystemJS module rewriting, and React JSX entity handling. The most notable behavioral change is minifier logic around preserving identifiers used in `for (...)` initialization, plus a SystemJS rewriting change affecting assignment pattern targets.
v1.16.1-nightly-20260819.1
Release v1.16.1-nightly-20260819.1 was published on 2026-08-19, but no release notes were provided by the publisher. As a result, there is no documented information about new features, fixes, or breaking changes in this build.
v1.16.0
v1.16.0 contains substantial internal and wasm binding refactors, most notably around AST shape for function bodies and TypeScript this-parameter modeling. No publisher release notes were provided, so key behavioral and type-shape changes must be inferred from the code diff (including conservative React compiler detection on parse errors).
v1.16.0-nightly-20260814.1
This release is a nightly build, v1.16.0-nightly-20260814.1. No release notes were provided by the publisher, so there are no documented changes, fixes, or migration steps to confirm from the release description.
v1.15.47
Release v1.15.47 was published on 2026-07-29, but no release notes were provided by the publisher. The code diff shows a mix of React compiler configuration additions, AST macro option support, internal diagnostic reporter refactoring, and broad internal crate version bumps.
v1.15.47-nightly-20260729.1
This is a nightly build (v1.15.47-nightly-20260729.1) with no release notes provided by the publisher. Because no change log is available, the upgrade impact cannot be determined from the release notes alone, and you should review the corresponding commits and diff to identify any API, behavior, or configuration changes.
v1.15.46
No publisher release notes were provided for v1.15.46. The diff primarily shows build and packaging pipeline updates, along with internal changelog entries indicating code-behavior fixes in several SWC transforms.
v1.15.46-nightly-20260719.1
This nightly release bumps the SWC Rust/wasm package versions from 1.15.45-nightly-20260719.1 to 1.15.46-nightly-20260719.1. The diff also shows a CI/publish pipeline change to use Node.js 24 instead of Node.js 20 when publishing the npm packages, and it updates changelog entries for multiple SWC transforms.
v1.15.45-nightly-20260719.1
This nightly release includes substantial internal changes to SWC transformation configuration and adds new JavaScript bindings for Node.js support in WASM. It also introduces new React compiler linting APIs in the Node binding, while removing some rkyv-based serialization implementations from core AST-related crates.
Featuresv1.15.43
No publisher release notes were provided for v1.15.43. The code diff shows this release is primarily a coordinated version bump across SWC core and npm/WASM packages, along with an important build configuration change to the React compiler's use of swc_ecma_parser.
v1.15.43-nightly-20260622.1
This is a nightly build release (v1.15.43-nightly-20260622.1) for which no publisher release notes were provided. As a result, there is no documented information about new features, breaking changes, bug fixes, security, or dependency updates in the release notes.
v1.15.42-nightly-20260622.1
No release notes were provided for v1.15.42-nightly-20260622.1. The code diff shows a sizable internal update, most notably adding React Compiler configuration and a new integration path during transformation, alongside significant changes to Node binding tracing initialization behavior.
BreakingFeaturesv1.15.41
Release v1.15.41 does not include any publisher-provided release notes. The code diff shows significant internal changes, especially in the Node bindings for how parsed ASTs are serialized and later printed/transformed, including span rebasing via a new source-context envelope. There are also notable changes to atom equality implementations and to swc_common SourceFile hashing fields.
Featuresv1.15.41-nightly-20260609.1
No release notes were provided for v1.15.41-nightly-20260609.1, so the specific functional, API, or behavioral changes are not documented in the publisher material. Developers should review the corresponding code changes/PRs directly (or compare tags) to identify any breaking changes, dependency updates, or security fixes.
v1.15.40
No release notes were provided for v1.15.40. The diff shows this release is primarily a version bump across SWC-related JS packages and Rust bindings, plus a small CI/workflow script change in the swc-ecosystem-ci tooling.
v1.15.40-nightly-20260523.1
This release is v1.15.40-nightly-20260523.1, but no release notes were provided by the publisher. As a result, there is no documented information here about new features, bug fixes, security updates, or breaking changes.
v1.15.39-nightly-20260523.1
This nightly release (v1.15.39-nightly-20260523.1) primarily updates package versions across multiple @swc and binding crates, and refreshes Cargo.lock to pull in updated build components. The only clearly behavior-relevant code/config change visible in the diff is an update to the @swc/minifier npm test command.
v1.15.38-nightly-20260522.1
No release notes were provided for v1.15.38-nightly-20260522.1, so there is nothing documented to compare against. The code diff shown is dominated by CI and GitHub Actions infrastructure changes (new composite action inputs, pnpm-based dependency installation, stricter workflow permissions), plus new internal agent scripts.
BreakingSecurityv1.15.33
Release v1.15.33 provides no publisher release notes. The code diff shows a new workspace crate (swc-ast-explorer) plus changes to SWC minification behavior and multiple internal dependency version bumps (parser, minifier, core).
v1.15.33-nightly-20260502.1
This is a nightly build release (v1.15.33-nightly-20260502.1) published on 2026-05-02. The publisher did not provide any release notes, so no specific developer-impacting changes (features, fixes, breaking changes, or security updates) can be reliably identified from the provided data.