tsconfig.json

{
  "compilerOptions": {
    "rootDir": "src",
    "target": "es2018",
    "module": "NodeNext",
    "outDir": "./dist/esm" /* Redirect output structure to the directory. */,
    "strict": true /* Enable all strict type-checking options. */,
    "noFallthroughCasesInSwitch": true /* Report errors for fallthrough cases in switch statement. */,
    "declaration": true,
    "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. */,
    "forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */
  },
  "include": ["src/**/*.ts"],
  "exclude": ["src/**/*.spec.ts"]
}