Sharing you all a quick & simple tool I have made with Envato API and Github API.
Now you can automatically Invite Collaborators to your Private Github Repo based on Envato Market Purchases using Github API & Envato API
See Live Demo: http://git-access.surjithctly.in/
Its Open Source
Github Link: https://github.com/surjithctly/github-repo-access
The Cool thing is you can host this without any server using Vercel. Its written on Node JS Serverless Technology so that your API Tokens are Safe.
Fork & Make your own version. Let me know your thoughts.