tsconfig.base.json

{
  "compilerOptions": {
    "allowJs": false,
    "declaration": true,
    "inlineSources": true,
    "jsx": "react",
    "module": "commonjs",
    "moduleResolution": "node",
    "noEmit": true,
    "noImplicitAny": true,
    "noImplicitReturns": true,
    "noUnusedLocals": false,
    "noUnusedParameters": false,
    "outDir": "./test-ts",
    "removeComments": false,
    "sourceMap": true,
    "strictNullChecks": true,
    "target": "es6"
  },
  "exclude": ["typings/preact"]
}