tsconfig.json

{
  "compilerOptions": {
    "target": "es6",
    "module": "commonjs",
    "outDir": "./build",
	  "strict": false,
	// If strict is set to true, set strictPropertyInitialization = false (from @https://update.angular.io/?l=2&v=5.2-6.0)
    "moduleResolution": "node",
    "esModuleInterop": true,
    "sourceMap": true,
    "declaration": false,
    "allowJs": true,
    "noImplicitAny": false,
    "noUnusedLocals": true,
    "noImplicitThis": true,
    "strictNullChecks": true,
    "noImplicitReturns": true,
    "preserveConstEnums": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "suppressImplicitAnyIndexErrors": true,
	"forceConsistentCasingInFileNames": true,
    "lib": [
      "es2018",
      "dom"
    ],
    "types": [ "node", "jest" ]
  },
  "exclude": [
    "node_modules",
    "build",
    "ecosystem.config.js"
  ]
}