libgit2.org

Libgit2 is a Git library written in portable C, with subsets of C99 to rapidly build Git functionality in any language. It has permissive licensing, extensive testing, and supports various popular OS and hosting services. Users can interact with it directly or use language bindings to handle native code calls. It manages Git repositories, handles abstracted ODB backend systems, and various other functions like error messages, threading support, and API calls. It can perform over 175 different functions.