How to get the devServer proxy to work?

module.exports = {
  devServer: {
    proxy: {
      '^/auth': {
        target: 'http://localhost:3000',
        ws: true,
        changeOrigin: true,
      },
    },
  },
};

I’ve configured my vue.config.js in the root of the project.

When I run:

npm run serve - the proxy works
vue-cli-service serve - the proxy works
ionic serve - the proxy does not work

what could be the issue? doesn’t ionic use the vue cli under the hood?