Automatic `nix-shell -p` on command not found

[lexa]

I search here programs.command-not-found.enable - MyNixOS
then enable in /etc/nixos/configuration.nix

`command-not-found` unable to open database

Huh, apparently running sudo nix-channel --update got me the programs.sqlite database. $ sudo nix-channel --update $ cat /nix/var/nix/profiles/per-user/root/channels/nixos/.git-revision 573095944e7c1d58d30fc679c81af63668b54056 $ ls -l /nix/var/nix/profiles/per-user/root/channels/nixos/programs.sqlite -r--r--r-- 1 root root 10076160 Jan 1 1970 /nix/var/nix/profiles/per-user/root/channels/nixos/programs.sqlite So now the question is, is running nix-channel --update at least once required? O…

sudo nix-channel --update

[nix@nixos:~]$ htop
The program 'htop' is not in your PATH. It is provided by several packages.
You can make it available in an ephemeral shell by typing one of the following:
  nix-shell -p htop
  nix-shell -p htop-vim

[nix@nixos:~]$ export NIX_AUTO_RUN=1

[nix@nixos:~]$ export NIX_AUTO_RUN_INTERACTIVE=1

[nix@nixos:~]$ htop
Select a package that provides 'htop':
  [1]: htop
  [2]: htop-vim
Your choice [1-2]: ^C

[nix@nixos:~]$