.tsconfig.json

{
  "compilerOptions": {
    "target": "es2017" /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017','ES2018' or 'ESNEXT'. */,
    "module": "commonjs" /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */,
    "lib": ["dom", "ES2015"] /* Specify library files to be included in the compilation. */,
    "sourceMap": true /* Generates corresponding '.map' file. */,
    "resolveJsonModule": true,
    "strictNullChecks": true /* Stricter type-checking for nullable objects */,
    "noImplicitAny": true /* Raise error on expressions and declarations with an implied as2 type */,
    "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
    "declaration": true,
    "skipLibCheck": true,
    "outDir": "./dist",
    "rootDir": "src"
  },
  "exclude": ["node_modules", "test", "example"]
}