Nix’s payoff is moving to use it for dev projects as well as your base OS config. I’ve been using it instead of the standard mix of brew/bundler/nvm/etc. everyone uses to setup their development environment for React native or instead of pip/venv and couldn’t be happier: no globally installed tools with conflicting versions, just a .envrc and a shell.nix in each project. (No one else on the team uses nix this way, but, in a year or so, I’ve not run into any issues)