tsconfig.json

{
  "compilerOptions": {
    "outDir": "./build/",
    "noImplicitAny": true,
    "strictNullChecks": false,
    "module": "es6",
    "target": "es6",
    "lib": [
      "es2019",
      "DOM"
    ],
    "jsx": "preserve",
    "allowJs": true,
    "moduleResolution": "node",
    "allowSyntheticDefaultImports": true,
    "sourceMap": true
  },
  "exclude": ["node_modules"],
  "include": ["src", "index.d.ts"]
}