omnimodModular codemods for the web

A small core plus plugins — fast, formatting-preserving, and easy to extend.

Formatting-preserving

oxc-parser (UTF-16 offsets) + magic-string splices keep untouched code byte-identical, and generated code is run through your project's own formatter.

Plugin architecture

A two-phase analyze → transform → finalize lifecycle with shared cross-file state. Author a plugin with definePlugin and a single transform function.

Seven plugins included

styled→vanilla-extract, moment→dayjs, jest→vitest, lodash→es-toolkit, redux→Redux Toolkit, React class→hooks, and webpack→vite. Convertible cases are automated; the rest is flagged with TODOs and AI-ready migration guides.