It may be that at one time portions of git were written in Perl, but at this point the git/git repo is all C and Bash, with the exception of some small amount of Perl code bundled in the repo that looks to serve the purpose of providing for git integration into Perl code.

Update:

According to the git repo, Perl comprises about 6.6% of the repository, so it's maybe more than what I saw at first. The breakdown is:

• C - 48.6%
• Shell - 36.1%
• Perl - 6.6%
• Tcl - 4.5%
• Python - 2.0%
• Makefile - 0.8%
• Other - 1.4%

I suppose, given that git uses git for its own version control, we should be able to look at earlier points in the software's life cycle to see how those numbers changed over time. But I'm not sure how they are being generated for the current snapshot. Might be a fun thing to investigate someday.