tsconfig.base.json

{
  "compilerOptions": {
    "strict": true,
    "allowJs": true,
    "checkJs": false,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "allowSyntheticDefaultImports": true,
    "forceConsistentCasingInFileNames": true,

    // From https://www.typescriptlang.org/docs/handbook/babel-with-typescript.html to use Babel for transpiling, tsc for types
    // Ensure that .d.ts files are created by tsc, but not .js files
    "declaration": true,
    "emitDeclarationOnly": true,
    // Ensure that Babel can safely transpile files in the TypeScript project
    "isolatedModules": true
  },
  "include": ["**/*"],
  "exclude": ["../node_modules"]
}