Group `nixbld` existed but had a different gid (996) than planned (30000) about nix-installer

[cole-h]

This sounds like you previous installed Nix somehow. If you used the official scripts, you may need to follow their uninstallation steps: https://nix.dev/manual/nix/stable/installation/uninstall.html#uninstalling-nix

If you're feeling adventurous, it may work if you specify the nixbld group gid to the already-existing one:

$ curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install --nix-build-group-id 996

but I can't guarantee other things won't break.

[Forecastr-sci]

Thank you, I tried using official installation script and it also reported that group nixbld already exists. I had to delete all the users in that group and then delete the group itself using shell script found here: https://discourse.nixos.org/t/i-have-removed-all-nixbld-users-and-nixbld-group-by-excute/46062
for i in $(seq 1 32); do sudo userdel nixbld$i done sudo groupdel nixbld

I'm not sure why that could happen, but I installed Devbox before using your script and yes, there were several attempts to install nix with official script before this one