Typescript module resolution not working

You are having the same problem as many others, the belief that the TypeScript compiler will save the resolved paths to the JS files. That is not the case. You will need to resolve this on your own, or by using a tool, WebPack is often what people suggest (WebPack, however, is a monster), please see this answer:

Typescript2 path module resolution

This will most likely solve your problem as well!

Of course in your case node gets confused about the module, because it expects all non-relative paths to be present in node_modules. The good solution with typescript is to use paths section of tsconfig like this:

{
  "compilerOptions": {
    "paths": {
        "@utils": [
            "src/utils/*"
        ]
    }
  }
}

now we can

import { IntHelper } from '@utils/IntHelper';

but we still have to notify webpack or node about out path configuration:

// for node:
--require tsconfig-paths/register

// for webpack
const TsConfigPathsPlugin = require('awesome-typescript-loader').TsConfigPathsPlugin;


      resolve: {
        plugins: [
          new TsConfigPathsPlugin(),
        ]
      },