tsconfig.json

{
  "compilerOptions": {
    "moduleResolution": "node",
    "target": "es5",
    "module": "es2015",
    "lib": [
      "es2015",
      "es2016",
      "es2017",
      "dom"
    ],
    "strict": true,
    "sourceMap": true,
    "declaration": true,
    "allowSyntheticDefaultImports": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "typeRoots": [
      "node_modules/@types"
    ]
  },
  "exclude": [
    "node_modules",
    "**/*.spec.ts"
  ]
}