tsconfig.json

{
    "compilerOptions": {
        /* Visit https://aka.ms/tsconfig.json to read more about this file */

        /* Basic Options */
        // "incremental": true,                   /* Enable incremental compilation */
        "target": "es2015",                       /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */
        "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */

        /* js compiles to */
        "outDir": "lib",

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

        /* Module Resolution Options */
        "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
        "esModuleInterop": true,                  /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */

        /* Advanced Options */
        "skipLibCheck": true,                     /* Skip type checking of declaration files. */
        "forceConsistentCasingInFileNames": true,  /* Disallow inconsistently-cased references to the same file. */
        "declaration": true
    },
    "exclude": ["node_modules", "**/test/*", "lib"], // This is what fixed it!] // which files to skip
}