Use environment to set proxy.config.js property for ng serve

Title pretty much sums it up. I've got a proxy.conf.js file that gets hit on ng serve and I just want to grab the target url from the environment ts file, or a json file, or I don't really care at this point, I just want one place to store the URL that feeds the others respectively...

So environment.dev.ts;

export const environment = {
    production: false,
    apiUrl: 'http://localhost:12345'
};

Then proxy.conf.js;

var settings = require('./src/environments/environment.dev');

const PROXY_CONFIG = [{
    "/restapi/*": {
      "target": settings.environment.apiUrl,
      "secure": false,
      "changeOrigin": true,
      "logLevel": "debug"
    }
}]

module.exports = PROXY_CONFIG

Which for some reason I obviously don't understand (especially since intellisense fills in the path just fine for both the file and the property) I get error on ng serve;

Cannot find module './src/environments/environment.dev'
Error: Cannot find module './src/environments/environment.dev'
    at Function.Module._resolveFilename (module.js:547:15)
    at Function.Module._load (module.js:474:25)
    at Module.require (module.js:596:17)
    at require (internal/module.js:11:18)
........

So my question is, why can it not resolve this way? I just want one file to set the target URL on that feeds the places it's needed from environment.dev.ts

from Use environment to set proxy.config.js property for ng serve