In this lightning talk, Sergii will dive into the internals of the Git protocol and share his experience implementing a Git SSH server in Go using the excellent gliderlabs/ssh library. This specifically covers the internal workings of `git clone` operation and the steps Git normally does during its `git-upload-pack` operation. He’ll show some simple Go code that receives SSH requests and walks the Git commit graph to select objects to send back to the client.

GopherCon (Gopher Academy)

A GopherCon 2025 talk demonstrating how to build a minimal Git server in Go from scratch in under 7 minutes. The speaker walks through how `git clone` works internally, covering the `git-upload-pack` protocol, SSH server setup using the gliderlabs/ssh library, and the binary format of Git's pack and index files. Key implementation details include reading advertised references, parsing the .idx file structure, streaming pack file objects to the client, and a subtle bug fix involving zlib's ReadByte requirement that required replacing a TeeReader with a custom TeeByteReader. The final implementation is roughly 300 lines of Go code.

GopherCon 2025: Git Server from Scratch in Go - Sergii Iefremov