tsconfig.build.json

{
  "compilerOptions": {
    "target": "es5",
    "lib": ["es2015", "es2017"],
    "module": "commonjs",
    "moduleResolution": "node",
    "allowSyntheticDefaultImports": true,
    "allowJs": true,
    "importHelpers": true,
    "jsx": "react",
    "alwaysStrict": true,
    "sourceMap": false,
    "forceConsistentCasingInFileNames": true,
    "noFallthroughCasesInSwitch": true,
    "noImplicitReturns": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noImplicitAny": false,
    "noImplicitThis": false,
    "strictNullChecks": false,
    "outDir": "lib"
  },
  "include": ["src/**/*", "__tests__/**/*"],
  "exclude": ["./src/**/*.spec.ts", "./src/**/*.test.ts"]
}