mau\Lu is a fairly simple URL shortening backend written in Go. The first versions also contain support for a frontend. The code at commit 3fc7b2d is confirmed to work with a basic HTML-only frontend.

A fancy frontend can be found from mau.lu. I might release the frontend properly at some point. For now, the sources of mau.lu are available at maunium/mau.lu.

See the OpenAPI spec https://spec.maunium.net/maulu for the API details.