PostCSS JS is a PostCSS-based tool for working with CSS-in-JS, letting you process style objects and use PostCSS plugins such as Stylelint and RTLCSS. It can compile CSS-in-JS to CSS, convert CSS to CSS-in-JS (objectify), and parse style objects into a PostCSS Root for further processing.
Project status
- Active maintenance: The repo shows continuing updates, with a recent update on 2026-02-13 (5.1.0) and an additional upstream push on 2026-04-21, indicating it is not dormant.
- Update cadence: There were multiple updates clustered in late 2025 (Sep to Dec) and then another update in early 2026, suggesting an overall cadence of roughly every few weeks to a few months rather than long quiet periods.
AI summary generated
Recent updates
5.1.0
Release 5.1.0 is described as adding TypeScript types. However, the diff also includes runtime JavaScript changes in the parser and objectifier modules, plus updates to dev tooling and lockfiles.
Features5.0.3
Release 5.0.3 primarily focuses on performance and dependency reduction for the `objectifier` module. The release notes say it reduced dependencies and sped up `objectifier`, with no mention of behavior changes.
5.0.2
Release 5.0.2 is documented as a performance improvement, specifically that “dashify” was made much faster. The code diff confirms a major reimplementation of dashify (regex-based replacements replaced with a manual character loop), plus several CI workflow and dev dependency updates.
Breaking5.0.1
Release 5.0.1 updates postcss-js objectifier behavior when the `stringifyImportant` option is enabled, specifically around handling of multiple declarations with and without `!important`. The main change is in the merge logic used when combining rules for the same selector/property.
5.0.0
Release 5.0.0 primarily updates runtime support and CI configuration. The release notes document dropping Node.js 12, 14, 16, and 18 support, and the diff confirms that change while also tightening the supported Node.js version range.
Breaking4.1.0
Release 4.1.0 adds a new `stringifyImportant` option. This likely affects how certain values are serialized when using the relevant functionality, but the release notes do not describe behavior changes or defaults.
Features