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Latest Results

fix(es/parser): preserve type references named asserts before line breaks
fix/parser-asserts-linebreak
6 minutes ago
perf(es/preset-env): Reduce binary size with browserslist deflate (#12381) **Description:** Reduce the native binary size by upgrading `browserslist-rs` from 0.20.0 to 0.21.2 and explicitly enabling `deflate` for its bundled browser data. `@swc/core` `.node` release size on `aarch64-apple-darwin`: | Configuration | Bytes | MiB | | --- | ---: | ---: | | browserslist-rs 0.20.0 | 26,662,128 | 25.43 | | browserslist-rs 0.21.2 + deflate | 24,185,488 | 23.07 | | Reduction | **2,476,640** | **2.36 (9.29%)** | Both builds used `cargo build --release --locked -p binding_core_node`, default features (`swc_v1`, `plugin`), the repository toolchain (`nightly-2026-04-10`), and the unchanged release profile (fat LTO, stripped symbols, one codegen unit, panic abort). The baseline is `baf0ba6ee4`; both builds used the same checkout path. These are raw native library sizes and measure the combined version upgrade and deflate change. Both `.node` libraries loaded through the `@swc/core` JavaScript API and produced identical outputs for six browser-target queries, including `supports`, regional usage, and baseline queries. **BREAKING CHANGE:** For Rust consumers, `BrowserData::parse_versions` now accepts `browserslist::Distrib` from browserslist-rs 0.21 instead of 0.20, also exposed through `swc_core::ecma::preset_env`. The changeset marks `preset_env_base` and `swc_core` as major. **Related issue (if exists):** - [browserslist-rs v0.21.2 release notes](https://github.com/browserslist/browserslist-rs/releases/tag/v0.21.2) - [#50: Drop derivable caniuse data](https://github.com/browserslist/browserslist-rs/pull/50) - [#52: Compress data using deflate](https://github.com/browserslist/browserslist-rs/pull/52) - [#53: Deflate more data](https://github.com/browserslist/browserslist-rs/pull/53) - [#54: Improve deflate binary size](https://github.com/browserslist/browserslist-rs/pull/54)
main
22 minutes ago
chore: Add changeset
chenjiahan:chenjiahan/browserslist-deflate
57 minutes ago
test(es/lexer): remove dedicated tuple parser tests
fix/parser-mixed-tuple-elements
7 hours ago

Latest Branches

CodSpeed Performance Gauge
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fix(es/parser): preserve type references named asserts before line breaks#12372
47 minutes ago
e9e1bd7
fix/parser-asserts-linebreak
CodSpeed Performance Gauge
0%
perf(es/preset-env): Reduce binary size with browserslist deflate#12381
1 hour ago
c7b817e
chenjiahan:chenjiahan/browserslist-deflate
CodSpeed Performance Gauge
0%
7 hours ago
210c062
fix/parser-mixed-tuple-elements
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