[JZL003]

Not quite the same but very useful for me. Sometimes small patches to programs have big usability wins. In nix you can still update automatically, it adds your patch, automatically downloads the programs needed to compile (but still can be garbage collected afterwards), compiles and done

Maybe not great for production but for personal use, since I guess this patch could break. But in exchange for a few times it breaks, I get automatic patched updated

(Except for emacs where takes 40 minutes to compile, but schedule updated for night)