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perf(es/minifier): reuse ProgramData across compress iterations Keep one ProgramData on the compressor and re-analyze into it so top-level map/vec capacities are retained between hoist and fixed-point passes instead of allocating a fresh analysis each time. Co-authored-by: Cursor <cursoragent@cursor.com>

hamidrezahanafi:perf/minifier-analyze-into

1 hour ago

docs(changeset): add changeset for trivial object spread optimization Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lukesandberg:lukesandberg/drop_trivial_spreads

2 hours ago

Expand support for trivial spreads

lukesandberg:lukesandberg/drop_trivial_spreads

2 hours ago

perf(ts/fast-strip): defer diagnostic reporter setup

fix/type-strip-utf16

6 hours ago

chore(ts/fast-strip): add changeset for UTF-16 fix

fix/type-strip-utf16

8 hours ago

feat(es/react-compiler): expose `reactCompiler.environment.enableFunctionOutlining` (#12030) **Description:** The Babel React Compiler lets consumers configure `environment` options, but SWC's `reactCompiler` config previously exposed none of them — the compiler's `EnvironmentConfig` was always left at its defaults, unreachable from `.swcrc`. This adds a curated `environment` object to the `reactCompiler` config that mirrors Babel's `reactCompiler.environment` shape. It currently exposes a single field, `enableFunctionOutlining`, wired through to `EnvironmentConfig::enable_function_outlining`: ```json { "jsc": { "transform": { "reactCompiler": { "environment": { "enableFunctionOutlining": false } } } } } ``` The object is a deliberate allowlist rather than a passthrough of the full `EnvironmentConfig`: unset fields leave the compiler defaults untouched, so a partial object overrides only what it names, and the public surface stays small and intentional. New fields can be added one at a time as they are wired and tested. `EnvironmentConfig` is re-exported from `swc_ecma_react_compiler` so the config layer can name the type (it was already reachable via the public `PluginOptions.environment`). Tests: - unit test covering `environment.enableFunctionOutlining` deserialization; - fixture `environment-function-outlining-disabled`: with outlining off, a closure that captures a local binding stays inline; - fixture `environment-function-outlining-enabled`: with outlining on (default), a closure that captures nothing is outlined into a top-level helper. **BREAKING CHANGE:** None. `environment` is a new optional field; existing configs are unaffected. **Related issue (if exists):** N/A --------- Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

main

10 hours ago

chore: Add React Compiler environment changeset

imjordanxd:feat/react-compiler-enable-function-outlining

10 hours ago

refactor(es/typescript): track enum evaluation context

refactor/enum-evaluation-context

14 hours ago

Latest Branches

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perf(es/minifier): reuse ProgramData across compress iterations#12069

1 hour ago

0ba3702

hamidrezahanafi:perf/minifier-analyze-into

0%

Expand support for trivial spreads#12068

2 hours ago

766caa3

lukesandberg:lukesandberg/drop_trivial_spreads

+11%

fix(ts/fast-strip): preserve UTF-16 source positions#12067

6 hours ago

dfe16b3

fix/type-strip-utf16

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