Oh-my-zsh: Adding system-wide custom plugin

Help
1

I’m hoping to add a custom plugin to my configuration.nix so it gets added to all users. Currently, I have the following configuration which works:

  programs.zsh = {
    enable = true;
    enableGlobalCompInit = false;
    ohMyZsh = {
      enable = true;
      theme = "gentoo";
      customPkgs = with pkgs; [
        zsh-git-prompt
        zsh-nix-shell
        zsh-vi-mode
        zsh-completions
        zsh-command-time
        zsh-powerlevel10k
        zsh-fast-syntax-highlighting
        nix-zsh-completions
      ];
    };
  };

But now (and, right now preferably without home-manager because I want users to config their own home.nix and as I understand it, home-manager can’t both be globally installed (via configuration.nix) and by the user), I would like to add a plugin from GitHub: psgrep. How can I get this added, and load it?

2

Anyone who can help me with this, please?

3

I am suffering from this exact same problem as well. I want to install zsh-shift-select and I could get it to work.