After seeing all of the pushback and negative sentiment regarding GitHub and its poor reliability and everyone trying to move off of it, I decided to build this to make the transition easier.
It's the second half of a two-part project. Shotgun (https://github.com/ThatXliner/shotgun) diffs two OpenAPI specs and auto-maps what lines up, which turns out to be 60-80% of endpoints when both APIs are in the same domain. Anvil is the opinionated result of running that on GitHub vs Forgejo and then hand-fixing everything the auto-mapping got wrong or couldn't express.
Landing page with a demo: https://bryanhu.com/anvil/