next.js/turbopack/crates/turbopack-ecmascript-runtime/js/src/tsconfig.base.json

{
  "compilerOptions": {
    // type checking
    "strict": true,
    "noFallthroughCasesInSwitch": true,
    "noImplicitAny": true,
    "noImplicitReturns": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,

    // environment
    "target": "ESNext",

    // modules
    "baseUrl": ".",
    "module": "CommonJS",
    "types": [], // disable implicit types.

    // emit
    "noEmit": true,
    "stripInternal": true
  }
}