# Oxc crates_v0.146.0 — oxc crates_v0.146.0

- Product: Oxc (https://whatsnew.fyi/product/oxc)
- Vendor: Oxc
- Date: 2026-08-19
- Version: crates_v0.146.0
- Original notes: https://github.com/oxc-project/oxc/releases/tag/crates_v0.146.0
- Permalink: https://whatsnew.fyi/product/oxc/releases/crates-v0.146.0

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

---

- **added** — Improve negation of expressions in boolean context in minifier
- **fixed** — Narrow printSync input type in codegen
- **fixed** — Preserve unresolved parameter types in isolated-declarations
- **removed** — Remove deprecated test APIs from codegen
- **fixed** — Align enum template sourcemaps in codegen
- **changed** — Check sourceText only once in codegen for performance
- **changed** — Unwrap all unary expressions without creating dummy expressions in minifier
- **changed** — Remove loop from growMappingBuffer in codegen
- **changed** — Remove redundant branch in codegen
- **changed** — Make location passed to recordSourceMapping always a number in sourcemap
- **changed** — Take named-mapping only code off hot path in recordSourceMapping
- **changed** — Remove redundant setting of last in printImportAttributes and printIf
- **changed** — Combine 2 writes in printJSXElement

###### 🚀 Features

- 83cb516 minifier: Improve negation of expressions in boolean context (#25755) (Armano)

###### 🐛 Bug Fixes

- 82a790d codegen: Narrow printSync input type (#25871) (camc314)
- 134fb22 isolated-declarations: Preserve unresolved parameter types (#25909) (Dunqing)
- 526c2b3 codegen: Remove deprecated test APIs (#25889) (camc314)
- 344a9b2 codegen: Align enum template sourcemaps (#25872) (camc314)

###### ⚡ Performance

- 603b904 packages/codegen: Check `sourceText` only once (#25887) (overlookmotel)
- 5ef0c93 minifier: Unwrap all unary exprs without creating dummy expressions (#25891) (Armano)
- 8783524 packages/codegen: Remove loop from `growMappingBuffer` (#25886) (overlookmotel)
- b6b14c0 packages/codegen: Remove redundant branch (#25885) (overlookmotel)
- be6adf0 packages/sourcemap: Make `location` passed to `recordSourceMapping` always a number (#25884) (overlookmotel)
- f720f15 packages/codegen: Take named-mapping only code off hot path in `recordSourceMapping` (#25883) (overlookmotel)
- a734af5 packages/codegen: Remove redundant setting of `last` in `printImportAttributes` and `printIf` (#25882) (overlookmotel)
- c6e44c6 packages/codegen: Combine 2 writes in `printJSXElement` (#25881) (overlookmotel)
- 8801662 packages/codegen: Remove redundant mapping from `printParams` (#25880) (overlookmotel)

###### 📚 Documentation

- 5ad330e packages/codegen: Reformat comments (#25876) (overlookmotel)