sudo emacs /etc/nixos/configuration.nix
sudo nixos-rebuild switch &>nixos-switch.log || (
 cat nixos-switch.log | grep --color error && false)
gen=$(nixos-rebuild list-generations | grep current)
log=$(cat nixos-switch.log)
sudo cp /etc/nixos/configuration.nix .
git add .
git commit -m "$gen"
if (! log | grep error); then
    git push
fi