Works like nix-environments (see more info) that maintain out-of-tree shell.nix/flake.nix files.
It includes specific dependencies for build, develop or test and doesn't include user-specific dependencies, check shell.nix to see what it includes.
- most similar like Devflex that provides env for many projects: https://github.com/nix-community/nix-environments
- generates generic templates for different languages: https://github.com/kampka/nixify
- also templates for different languages: https://github.com/mrVanDalo/nix-shell-mix
- templates for flakes: https://github.com/NixOS/templates