go-git
go-git is a highly extensible git implementation library written in Go
...It's being actively developed since 2015 and is being used extensively by Keybase, Gitea or Pulumi, and by many other libraries and tools. After the legal issues with the src-d organization, the lack of update for four months and the requirement to make a hard fork, the project is now back to normality. The project is currently actively maintained by individual contributors, including several of the original authors, but also backed by a new company, gitsight, where go-git is a critical component used at scale. go-git aims to be fully compatible with git, all the porcelain operations are implemented to work exactly as git does.