tsconfig.json

{
    "compilerOptions": {
       "lib": [
          "es5",
          "es6"
       ],
       "allowJs": true,
       "target": "es5",
       "module": "commonjs",
       "moduleResolution": "node",
       "outDir": "./build",
       "rootDir": "./src",
       "strict": true,
       "noImplicitAny": true,
       "strictPropertyInitialization": false,
       "esModuleInterop": true,
       "resolveJsonModule":  true,
       "emitDecoratorMetadata": true, /* Enables experimental support for emitting type metadata for decorators. */
       "experimentalDecorators": true, /* Enables experimental support for ES7 decorators. */
       "sourceMap": true,
       /* Advanced Options */
       "skipLibCheck": true, /* Skip type checking of declaration files. */
       "forceConsistentCasingInFileNames": true,
       "typeRoots": ["./src/@types"]
    }
 }