tsconfig.base.json

{
  // https://www.npmjs.com/package/@tsconfig/node14
  "extends": "@tsconfig/node14/tsconfig.json",

  "compilerOptions": {
    "composite": true, // https://www.typescriptlang.org/docs/handbook/project-references.html

    "moduleResolution": "node", // modern
    "module": "commonjs",
    "declaration": true /* Generates corresponding '.d.ts' file. */,
    "declarationMap": true /* Generates a sourcemap for each corresponding '.d.ts' file. */,
    "sourceMap": true /* Generates corresponding '.map' file. */,
    "resolveJsonModule": true, // allow importing JSON files
    "experimentalDecorators": true, // enable decorators
    "emitDecoratorMetadata": true, // for runtime use of decorators (typeORM)
    // "baseUrl": "packages", // allow absolute path imports for all project packages
    "strictPropertyInitialization": false, // for TypeORM
    // "noUnusedLocals": true /* Report errors on unused locals. */,
    // "noUnusedParameters": true /* Report errors on unused parameters. */,
    "noImplicitReturns": true /* Report error when not all code paths in function return a value. */,
    "noFallthroughCasesInSwitch": true /* Report errors for fallthrough cases in switch statement. */,
    "noImplicitOverride": true // must use override
  }
}