[1.0.3] - 2026-05-27

🚀 Features

• transform: respect decorator strictNullChecks option (feat(transform): respect decorator strictNullChecks option #9580) by @kylecannon
• drop defer keyword (feat: drop defer keyword #9503) by @TheAlexLichter

🐛 Bug Fixes

• ci: create target dir before cargo release-oxc update (fix(ci): create target dir before cargo release-oxc update #9584) by @shulaoda
• ci: reorder prepare-release steps to avoid dirty git check failure (fix(ci): reorder prepare-release steps to avoid dirty git check failure #9583) by @shulaoda
• testing: canonicalize temp dir early and use platform-specific separator in test262 (fix(testing): canonicalize temp dir early and use platform-specific separator in test262 #9582) by @shulaoda
• testing: resolve symlinked temp dir in test262 snapshot normalization (fix(testing): resolve symlinked temp dir in test262 snapshot normalization #9581) by @shulaoda
• testing: canonicalize temp dir path in test262 snapshot normalization (fix(testing): canonicalize temp dir path in test262 snapshot normalization #9579) by @shulaoda
• dev: onOutput called twice when initial build fails (fix(dev): onOutput called twice when initial build fails #9552) by @hyf0
• dev: make ensureCurrentBuildFinish not returning error when engine closes (fix(dev): make ensureCurrentBuildFinish not returning error when engine closes #9564) by @h-a-n-a
• oxc-runtime: route require() to CJS helper variant ([Bug]: Class fields in CJS-classified modules bind _defineProperty to namespace via __toCommonJS, throwing at init #9263) (fix(oxc-runtime): route require() to CJS helper variant (#9263) #9526) by @IWANABETHATGUY
• generator: use exporter chunk's export mode for CJS default re-exports ([Bug]: With preserveModules, CJS emit forwards namespace object instead of .default for export { default as X } from #9299) (fix(generator): use exporter chunk's export mode for CJS default re-exports (#9299) #9529) by @IWANABETHATGUY
• rolldown: always run reduced-atom static cycle check ([Bug]: CJS subpath import in lazy chunk throws "X is not a function" — chunk-split interop mismatch in rolldown 1.0.0 / 1.0.1 #9441) (fix(rolldown): always run reduced-atom static cycle check (#9441) #9514) by @IWANABETHATGUY
• apply transform.dropLabels before scanning ([Bug]: transform.dropLabels does not prevent dynamic imports inside dropped blocks from being resolved #9521) (fix: apply transform.dropLabels before scanning (#9521) #9522) by @IWANABETHATGUY
• rolldown_watcher: take rolldown dep through the workspace (fix(rolldown_watcher): take rolldown dep through the workspace #9510) by @Boshen
• cache: keep the scan-stage cache consistent when a build fails (fix(cache): keep the scan-stage cache consistent when a build fails #9495) by @h-a-n-a
• skip JSON default-import namespace optimization for write targets (Panic in module finalizer when bundling @emoji-mart/data #9484) (fix: skip JSON default-import namespace optimization for write targets (#9484) #9489) by @IWANABETHATGUY
• deps: skip pnpm frozen-lockfile on Netlify to dodge catalog mismatch bug (fix(deps): skip pnpm frozen-lockfile on Netlify to dodge catalog mismatch bug #9471) by @Boshen

🚜 Refactor

• oxc-runtime: use Cow for helper path construction (refactor(oxc-runtime): use Cow for helper path construction #9538) by @IWANABETHATGUY
• fold import defer phase drop into PreProcessor (refactor: fold import defer phase drop into PreProcessor #9524) by @IWANABETHATGUY
• distinguish map: null vs map: undefined in transform hook output (refactor: distinguish map: null vs map: undefined in transform hook output #9497) by @sapphi-red

📚 Documentation

• explain the policy for Rust crates (docs: explain the policy for Rust crates #9547) by @sapphi-red
• cache: add design doc for cache (docs(cache): add design doc for cache #9544) by @h-a-n-a
• guide/troubleshooting: add TDZ error section (docs(guide/troubleshooting): add TDZ error section #9537) by @sapphi-red
• dev-engine: add design doc for dev-engine (docs(dev-engine): add design doc for dev-engine #9479) by @h-a-n-a
• lazy-barrel: tweak some words (docs(lazy-barrel): tweak some words #9483) by @shulaoda
• lazy-barrel: expand reasoning behind LARGE_BARREL_MODULES advice (docs(lazy-barrel): expand reasoning behind LARGE_BARREL_MODULES advice #9477) by @shulaoda

⚡ Performance

• generate: thread ast_table by value into codegen consumer (perf(generate): thread ast_table by value into codegen consumer #9555) by @Boshen
• finalizers: replace _reExport construction with a direct call to avoid calling clone_in (perf(finalizers): replace _reExport construction with a direct call to avoid calling clone_in #9501) by @Dunqing
• reorder hot-path boolean checks to short-circuit on cheap predicates first (perf: reorder hot-path boolean checks to short-circuit on cheap predicates first #9523) by @Boshen

🧪 Testing

• rolldown: regression fixture for [Bug]: circular import generated when using dynamic import and require #9401 (test(rolldown): regression fixture for #9401 #9418) by @IWANABETHATGUY
• failing test for [Bug]: CJS subpath import in lazy chunk throws "X is not a function" — chunk-split interop mismatch in rolldown 1.0.0 / 1.0.1 #9441 (test: failing test for #9441 #9504) by @TheAlexLichter

⚙️ Miscellaneous Tasks

• deps: upgrade oxc to 0.133.0 (chore(deps): upgrade oxc to 0.133.0 #9563) by @Dunqing
• deps: update crate-ci/typos action to v1.46.3 (chore(deps): update crate-ci/typos action to v1.46.3 #9576) by @renovate[bot]
• deps: update mimalloc-safe to 0.1.62 (chore(deps): update mimalloc-safe to 0.1.62 #9577) by @shulaoda
• mimalloc-safe: update to a bug-fix branch for verification (chore(mimalloc-safe): update to a bug-fix branch for verification #9569) by @shulaoda
• deps: update test262 submodule for tests (chore(deps): update test262 submodule for tests #9551) by @rolldown-guard[bot]
• point published crates' readme to root README.md (chore: point published crates' readme to root README.md #9553) by @Boshen
• replace actions-cool/issues-helper with gh CLI (ci: replace actions-cool/issues-helper with gh CLI #9543) by @Boshen
• deps: update cargo-shear to 1.12.4 (chore(deps): update cargo-shear to 1.12.4 #9541) by @Boshen
• deps: update taiki-e/install-action action to v2.79.4 (chore(deps): update taiki-e/install-action action to v2.79.4 #9535) by @renovate[bot]
• deps: update github actions (chore(deps): update github actions #9532) by @renovate[bot]
• deps: update rust crates (chore(deps): update rust crates #9534) by @renovate[bot]
• deps: update npm packages (chore(deps): update npm packages #9533) by @renovate[bot]
• gate experimental/testing-only items to silence dead_code in publish builds (chore: gate experimental/testing-only items to silence dead_code in publish builds #9517) by @Boshen
• docs: deploy to Void (ci(docs): deploy to Void #9509) by @Boshen
• release: set up cargo-release-oxc for publishing crates (chore(release): set up cargo-release-oxc for publishing crates #9476) by @Boshen
• rolldown_plugin_lazy_compilation: add missing description (chore(rolldown_plugin_lazy_compilation): add missing description #9507) by @Boshen
• mimalloc-safe: update to a bug-fix branch for verification (chore(mimalloc-safe): update to a bug-fix branch for verification #9506) by @shulaoda
• deps: update crate-ci/typos action to v1.46.2 (chore(deps): update crate-ci/typos action to v1.46.2 #9468) by @renovate[bot]

❤️ New Contributors

• @kylecannon made their first contribution in #9580