tsconfig.json

{
  "compilerOptions": {
    /* Basic Options */
    "target": "es2018",                       /* Good for Node 10 - https://github.com/microsoft/TypeScript/wiki/Node-Target-Mapping */
    "module": "commonjs",                     /* Ignored by rollup but used by ts-node for tests */
    "declaration": true,                      /* Generates corresponding '.d.ts' file. */

    /* Strict Type-Checking Options */
    "strict": true,                           /* Enable all strict type-checking options. */

    /* Additional Checks */
    "noUnusedLocals": true,                   /* Report errors on unused locals. */
    "noUnusedParameters": true,               /* Report errors on unused parameters. */
    "noImplicitReturns": true,                /* Report error when not all code paths in function return a value. */
    "noFallthroughCasesInSwitch": true,       /* Report errors for fallthrough cases in switch statement. */

    /* Module Resolution Options */
    "esModuleInterop": true                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
  }
}