tsconfig.json

{
  "compilerOptions": {
    "target": "es2019" /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */,
    "module": "commonjs" /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */,
    "declaration": true /* Generates corresponding '.d.ts' file. */,
    "sourceMap": true /* Generates corresponding '.map' file. */,
    "outDir": "lib" /* Redirect output structure to the directory. */,
    "rootDir": "src" /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */,
    "strict": true /* Enable all strict type-checking options. */,
    "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
    "skipLibCheck": true /* Skip type checking of declaration files. */,
    "noImplicitAny": false,
    "strictNullChecks": true,
    "forceConsistentCasingInFileNames": true,
    "lib": ["esnext.bigint", "ES2019"]
  },
  "compileOnSave": true
}