@evanyou: To answer a common question - why not make React Compiler a plugin? It all comes down to practical trade-offs. Making i…

To answer a common question - why not make React Compiler a plugin?

It all comes down to practical trade-offs. Making it a rust-based plugin is already significantly faster than the Babel version (up to 15x), but still 50% slower than direct-in-oxc due to the data passing / AST cloning overhead for being a plugin.

This is also different from e.g. Vue or Svelte where there are completely different AST formats; the React Compiler works on a JS/JSX AST that Oxc already supports (with only slight format differences). By integrating it in Oxc we can eliminate a lot of the AST cloning / transforming overhead, which isn’t feasible for other frameworks. It’d be a shame to leave such a big perf opportunity on the table.

We are also fully aware of how integrating it will result in bigger binary size for users who don’t use React Compiler, which is why I personally blocked the version that resulted in a ~5mb increase. We are aiming to get it down to a reasonable level while optimizing binary size across the board to minimize the downside.

For the long run, we are aiming to make raw AST transfer (which is already used in oxlint JS plugins) applicable to transform plugins. This would allow us to ship oxc plugins without AST cloning perf overhead.

Boshen (@boshen_c): We withdrew the Rust React Compiler integration from Rolldown and Vite because it increased the binary size from 28.7MB to 33.8MB, a 17% increase, which cannot be justified for all Vite users.

My current experiment is to have Claude understand our constraints.

Preliminary