@langri-sha/tsconfig

Shared TypeScript configurations that type-check TypeScript and JavaScript alike, with variants for monorepos, React and Emotion.

Usage

Install the necessary dependencies:

npm install -D typescript @langri-sha/tsconfig

Then extend the base configuration:

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "extends": "@langri-sha/tsconfig"
}

To combine configurations, list them in this order — later entries win:

1. A base: @langri-sha/tsconfig, @langri-sha/tsconfig/project.json for a package inside a monorepo, or @langri-sha/tsconfig/build.json for a library that emits, React or Emotion ones included.
2. @langri-sha/tsconfig/react.json for React.
3. @langri-sha/tsconfig/emotion.json for Emotion, which also needs react.json.

For example, an Emotion app inside a monorepo:

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "extends": [
    "@langri-sha/tsconfig/project.json",
    "@langri-sha/tsconfig/react.json",
    "@langri-sha/tsconfig/emotion.json"
  ]
}

The monorepo's root tsconfig.json extends the base and lists each package as a project reference:

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "extends": "@langri-sha/tsconfig",
  "references": [{ "path": "./packages/app" }]
}

Strictness and module options

TypeScript 6 or 7 is required. On top of their defaults, which include strict, the base sets, among others:

• verbatimModuleSyntax: import types with a type modifier. An import whose every named binding is an inline type, as in import { type Name } from 'module', still leaves import {} from 'module' in the output; import type { Name } from 'module' drops it.
• erasableSyntaxOnly: no enums, namespaces with values, parameter properties or angle-bracket type assertions. Set it to false in a package that needs them.
• noImplicitReturns and moduleDetection: "force".
• lib: ["ES2025"], which doesn't declare APIs Node 24 lacks, such as Temporal.

Emitting

The base only type-checks. It doesn't set rootDir, which TypeScript 6 no longer infers, so a project that emits through it fails with TS5011 when its sources sit in a subdirectory such as src. A project that emits JavaScript or declarations extends @langri-sha/tsconfig/build.json instead, which sets rootDir to src:

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "extends": "@langri-sha/tsconfig/build.json",
  "include": ["src"]
}

See

• @moonrepo/tsconfig

Contributing

See CONTRIBUTING.md in langri-sha/github.