tsconfig.json

{
  "compilerOptions": {
    "target": "es6",
    "module": "es6",
    "lib": ["esnext", "DOM"],
    "types": ["jest"],
    "declaration": true,
    "declarationMap": true,
    "experimentalDecorators": true,
    "sourceMap": true,
    "outDir": "dist",
    "importHelpers": true,
    "resolveJsonModule": true,
    "skipLibCheck": true,
    "strict": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "strictPropertyInitialization": true,
    "noImplicitThis": true,
    "alwaysStrict": true,
    "suppressImplicitAnyIndexErrors": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "moduleResolution": "node",
    "allowSyntheticDefaultImports": true,
    "esModuleInterop": true
  },
  "compileOnSave": true,
  "include": ["src"],
  "exclude": ["node_modules", "dist"]
}