@sanity/vanilla-extract-integration

A vendored port of @vanilla-extract/integration onto the rolldown toolchain, for the @sanity/vanilla-extract-* plugins. Same API for the surface they consume, none of the babel/esbuild machinery:

| Upstream | Here | | --------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- | | compile() bundles .css.ts graphs with an esbuild child compilation | a rolldown child compilation (in-memory, CommonJS, lazy-loaded) | | debug IDs injected by babel (@vanilla-extract/babel-plugin-debug-ids + @babel/plugin-syntax-typescript) | an AST pass over yuku-parser's oxc-shaped AST, spliced by offset so untouched code stays byte-identical | | module evaluation via the eval package | node:vm.compileFunction + node:module.createRequire | | find-up, dedent, mlly dependencies | inlined (walk-up loop, plain strings, vendored detectSyntax regexes) |

The only runtime dependencies left are rolldown (which the host toolchain — tsdown, Vite 8, or raw rolldown — ships anyway; the wide ^1.1.5 range lets package managers reuse the host's copy when its version satisfies it, though hosts pinning older minors can still resolve a second copy), yuku-parser (already transitive in rolldown-based toolchains through rolldown-plugin-dts), @vanilla-extract/css, and javascript-stringify.

API

import {
  compile, // rolldown child compilation of a .css.ts graph
  cssFileFilter,
  getPackageInfo,
  getSourceFromVirtualCssFile,
  normalizePath,
  processVanillaFile, // evaluate compiled output into virtual CSS imports + serialized exports
  resolveIdentifierOption, // turn the plugins' `identifiers` option (incl. 'safe') into an IdentifierOption
  serializeVanillaModule,
  transform, // debug IDs + file scope wrapping for a single module
  virtualCssFileFilter,
  type IdentifierOption,
  type PluginIdentifierOption,
} from '@sanity/vanilla-extract-integration'

Intentional differences from upstream:

• The plugins' identifiers option also accepts 'safe': 'short' identifiers whose file-scope hash is @emotion/hash(packageName + '@' + packageVersion + filePath), so releases of a package never share a class name. resolveIdentifierOption(identifiers, cwd) turns it into a custom identifier function, reading the version from the same package.json as the package name (getPackageInfo() now also returns version).

• The esbuildOptions bag of compile() is dropped (it leaked the esbuild API into the public surface).

• Only the API surface consumed by @sanity/vanilla-extract-rolldown-plugin and @sanity/vanilla-extract-vite-plugin is exported.

• The babel-compiled createTheme destructure special-cases of the debug-ID transform are not ported: the transform only ever sees authored source.

The parser bench-off

The debug-ID pass is parser-agnostic (one shared walker over the oxc-shaped TS-ESTree AST). bench/debug-ids.bench.ts compares yuku-parser against rolldown/parseAst over a generated corpus of hundreds of realistic .css.ts files, and the unit tests run every case through both parsers to prove identical output:

pnpm --filter @sanity/vanilla-extract-integration bench
# corpus size: VE_BENCH_DEBUG_IDS_FILES=2500 pnpm --filter @sanity/vanilla-extract-integration bench

Last measured (2026-07-16, Node 24.18.0, Linux x64, 4-core Intel Xeon; rolldown 1.1.5, yuku-parser 0.6.1): yuku-parser parses ~2x faster — 59.7ms vs 121.0ms mean per 500-file corpus pass, 278ms vs 593ms at 2500 files (cold import 9.0ms vs 6.6ms). yuku-parser ships as the production backend on that win; it's effectively free dependency-wise since the yuku toolchain is already in the install graph of rolldown-based setups (rolldown-plugin-dts, used by tsdown and @sanity/pkg-utils, parses with it). rolldown/parseAst stays in the bench (rolldown is a dependency regardless, for compile()) so the comparison remains reproducible as both parsers evolve.

License

MIT — incorporates code from vanilla-extract (MIT, Copyright (c) 2021 SEEK) and mlly (MIT). See LICENSE.