Nix Package Manager

Managing packages

nix-env -iA nixpkgs.<packagename>

NixOS

Updating a Flake based system

sudo nix update --flake /etc/nixos
sudo nixos-rebuild switch

Updating a non-Flake based system

sudo nixos-rebuild switch

You can use boot instead of switch for the system to boot into the new generation on reboot instead.

Contributing to nixpkgs

Updating packages that you maintain

git checkout -b bump-mypkg
nix-shell -p nix-update --run 'nix-update <pkg> --commit'
nix-build -A <pkg> # ensure it builds
git push <fork> bump-mypkg