tsconfig.json

{
    "compilerOptions": {
      "rootDirs": [ "./src" ],
      "outDir": "./build",
      "experimentalDecorators": true,
      "allowUnreachableCode": false,
      "allowUnusedLabels": false,
      "forceConsistentCasingInFileNames": true,
      "module": "commonjs",
      "declaration": true,
      "importHelpers": false,
      "noEmitOnError": true,
      "noFallthroughCasesInSwitch": true,
      "noImplicitReturns": true,
      "noUnusedLocals": true,
      "pretty": true,
      "inlineSourceMap": true,
      "noImplicitThis": true,
      "noImplicitAny": true,
      "strict": true,
      "strictNullChecks": true,
      "skipLibCheck": true,
      "target": "es2018",
      "esModuleInterop": true,
      "emitDecoratorMetadata": true,
      "resolveJsonModule": true,
      "lib": [
        "es2019"
      ]
    },
    "exclude": [
      "node_modules",
      "build",
      "coverage"
    ]
}