tsconfig.json

{
  "compilerOptions": {
    "target": "ES5" /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */,
    /* Modules */
    "module": "commonjs",
    "lib": ["ES6"],
    "rootDir": "src",
    "allowJs": true,
    "resolveJsonModule": true,
    /* Emit */
    "outDir": "./build",
    "removeComments": true,
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    /* Type Checking */
    "strict": true /* Enable all strict type-checking options. */,
    "noImplicitAny": true /* Enable error reporting for expressions and declarations with an implied 'any' type. */ /* Default catch clause variables as 'unknown' instead of 'any'. */,
    "alwaysStrict": true /* Ensure 'use strict' is always emitted. */ /* Disable error reporting for unreachable code. */ /* Skip type checking .d.ts files that are included with TypeScript. */,
    "skipLibCheck": true /* Skip type checking all .d.ts files. */
  }
}