@factorn/ts-config

Shared TypeScript compiler presets for Factorn projects.

Presets

All presets inherit from base.json unless noted.

base.json

Strict ES2025 settings with bundler module resolution, declaration output, and verbatimModuleSyntax. Suitable as a foundation or for packages that define their own include/compilerOptions on top.

tsdown.json

Extends base.json with noEmit: true. Use for packages built by tsdown where the bundler emits output.

node-library.json

Extends tsdown.json with types: ["node"]. For Node-targeted libraries.

ts-library.json

Extends tsdown.json with types: [] (explicit, though this is the TypeScript 7 default). For libraries that should not pull in ambient Node or DOM types.

react.json

Extends base.json with the DOM lib (which includes DOM.Iterable since TypeScript 6), react-jsx, noEmit, and the typescript-plugin-css-modules plugin for typed CSS module imports.

Note: the TypeScript 7 language server does not support language service plugins yet, so typed CSS modules only work in editors falling back to the TypeScript 6 language server. tsc builds are unaffected.

react-app.json / react-library.json

Aliases of react.json.

Usage

{
  "extends": "@factorn/ts-config/node-library.json",
  "compilerOptions": {
    "rootDir": "src",
    "outDir": "dist"
  },
  "include": ["src"]
}

TypeScript 7 notes

These presets target TypeScript 7 and rely on its new defaults:

• types defaults to [], so ambient type packages must be listed explicitly (as node-library.json does for @types/node).
• rootDir defaults to the directory containing your tsconfig.json. If your sources live in src/ and you emit with tsc, set rootDir: "src" in your own config (path options are resolved relative to the file that defines them, so presets cannot set it for you).
• esModuleInterop, allowSyntheticDefaultImports, alwaysStrict, and forceConsistentCasingInFileNames are always on and no longer set here.

Choosing a preset

| Project type | Preset | | --------------------------- | ---------------------------------------- | | Node library (tsdown) | node-library.json | | Generic TS library (tsdown) | ts-library.json | | React app or component lib | react-app.json or react-library.json | | Custom / non-standard build | base.json or tsdown.json |