Pijul (https://pijul.org/ https://pijul.org/) is based on a categorical theory of patches (https://arxiv.org/abs/1311.3903 https://arxiv.org/abs/1311.3903). It

Pijul (https://pijul.org/ https://pijul.org/) is based on a categorical theory of patches (https://arxiv.org/abs/1311.3903 https://arxiv.org/abs/1311.3903). It is similar to Darcs but written in Rust. They claim that Pijul has solved the exponential merge problem. The docs, FAQ, and blogs, in particular the last one, are interesting readings.