Co-Author here.
git-dit is a distributed issue tracker in/for git, currently implemented as proof-of-concept in Bash. If you want to play with it, make sure you use current git versions.
It differs from things like bugseverywhere and fossil in that it is a distributed issue tracker for git only, using git features to implement issue tracking in a way so that merging of issues, attaching issues to commits, creating PRs, etc is possible. It does explicitely _not_ store any "structured data" like JSON, YAML or such, but simply uses git commit messages for issue messages. So, E-Mail workflows, github, gitlab and other hosting platforms and their issue tracking schema can be adapted and mirrored into "git-dit", technically. We are not there yet, though. We are planning to reimplement the current featureset in a more robust language.
When playing with this, please keep in mind that this is a POC - there are bugs, missing things and rough edges. Do not use on a production repository!
I'd happily answer your questions!
I saw on your projects list that you plan to port it from shell to Rust. Nice choice. I had a great experience using Rust for git-series (https://github.com/git-series/git-series/ ); the git2-rs binding is a joy to use.
If you run into any issues along the way, or want some help with git2-rs, I'd be happy to chat about it. (And, of course, feel free to borrow anything from git-series; if you find something useful and non-trivial that you'd like to share, let me know and I can extract it into a crate.)