tsconfig.json

{
    "compilerOptions": {
        "module": "commonjs",
        "removeComments": true,
        "sourceMap": true,
        "target": "es6", // NodeJs v8.9.3 supports most of the "es6" features
        "pretty": true,
        "declaration": true,
        "outDir": "dist", // "./build",
        "experimentalDecorators": true,
        "emitDecoratorMetadata": true,
        "typeRoots": ["types"],
        "types": ["reflect-metadata", "node"],
        "moduleResolution": "node",
        "noImplicitReturns": true,
        // "allowJs": true,
        "suppressImplicitAnyIndexErrors": true,
        "allowSyntheticDefaultImports": true,
        "esModuleInterop": true // do not use `import * as service from '...'`, you must use `import service from '...'`
    },
    "include": [
        "src/**/*.ts"
    ],
    "exclude": [
        "node_modules",
        "**/node_modules/*",
        "**/*.spec.ts",
        "**/__tests__/*"
    ],
    "compileOnSave": false
}