This project needs libgit2, which is written in C so we need to build that as well. In order to build libgit2, you need `cmake`, `pkg-config` and a C compiler. You will also need the development packages for OpenSSL and LibSSH2 if you want to use HTTPS and SSH respectively.
Run `go get -d github.com/libgit2/git2go` to download the code and go to your `$GOPATH/src/github.com/libgit2/git2go` dir. From there, we need to build the C code and put it into the resulting go binary.
libgit2 uses OpenSSL and LibSSH2 for performing encrypted network connections. For now, git2go asks libgit2 to set locking for OpenSSL. This makes HTTPS connections thread-safe, but it is fragile and will likely stop doing it soon. This may also make SSH connections thread-safe if your copy of libssh2 is linked against OpenSSL. Check libgit2's `THREADSAFE.md` for more information.