tsconfig.json

{
  "compilerOptions": {
    // Target latest version of ECMAScript.
    "target": "esnext",
    // path to output directory
    "outDir": "./dist/",
    // enable strict null checks as a best practice
    "strictNullChecks": true,
    // Search under node_modules for non-relative imports.
    "moduleResolution": "node",
    // Process & infer types from .js files.
    "allowJs": true,
    // Don't emit; allow Babel to transform files.
    //"noEmit": true,
    // Enable strictest settings like strictNullChecks & noImplicitAny.
    "strict": false,
    // Import non-ES modules as default imports.
    "esModuleInterop": true,
    // use typescript to transpile jsx to js
    "jsx": "react",
    "baseUrl": "./src",
    "lib": [
      "es2015",
      "dom.iterable",
      "es2016.array.include",
      "es2017.object",
      "dom"
    ],
    "module": "es6",
    "removeComments": true,
    "alwaysStrict": true,
    "forceConsistentCasingInFileNames": true,
    "importHelpers": true,
    "typeRoots": [
      "src/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
  },
}