Developer activity is a small module that I just released on Drupal.org. It fetches local users activities on Drupal.org and on GitHub.com into custom entities.
Only public endpoints are used and they at each cron. So all you need are a Drupal.org user ID and a GitHub.com user name fields for your Drupal users (and of course install the dependencies, which is just Migrate plus 8.x-5.x.
You can then create Views with those custom entities, for instance.