tsconfig.json

{
    "compilerOptions": {
        /* Basic Options */
        "target": "es5"                       /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */,
        "module": "commonjs"                  /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */,
        "outDir": "./build"                   /* Redirect output structure to the directory. */,
        "sourceMap": true                     /* Generates corresponding '.map' file. */,

        /* Strict Type-Checking Options */
        "strict": true                        /* Enable all strict type-checking options. */,
        "noImplicitAny": true                 /* Raise error on expressions and declarations with an implied 'any' type. */,
        "alwaysStrict": true                  /* Parse in strict mode and emit "use strict" for each source file. */,
        "esModuleInterop": true               /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
        "strictPropertyInitialization": false /* Enable strict checking of property initialization in classes. */
    }
}