[nvarsj]

Exactly. direnv/lorri basically solves the per-language virtualenv nonsense, but universally for anything. I use chezmoi to manage my shell.nix for various directories. That way every project can manage its system libraries independently. Once you get used to it, it's truly amazing. So much so, I almost think the future trend, once enough people become enlightened, will be checking in shell.nix as standard for development projects.