tsconfig.json

{
  "compilerOptions": {
    "module": "commonjs",
    "target": "es5",
    "lib": ["es5", "es6", "es7", "es2017", "dom", "ESNext"],
    "sourceMap": true,
    "allowJs": true,
    "jsx": "react",
    "moduleResolution": "node",
    "baseUrl": "./",
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "noImplicitReturns": true,
    "noImplicitThis": true,
    "noImplicitAny": false,
    "strictNullChecks": true,
    "skipLibCheck": true,
    "suppressImplicitAnyIndexErrors": true,
    "noUnusedLocals": true,
    "noUnusedParameters": false,
    "declaration": true,
    "allowSyntheticDefaultImports": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "resolveJsonModule": true,
    "downlevelIteration": true,
    "typeRoots": ["node", "node_modules/@types", "src/typings"],
    "outDir": "esm",
    "module": "es6",
    "target": "es6",
    "declaration": true,
    "preserveConstEnums": true,
    "sourceMap": false,
    "rootDirs": ["src"]
  },
  "include": ["src/*"],
  "exclude": ["node_modules", "src/__tests__/*"]
}