An alternative solution to direnv dropping aliases and functions

Direnv does not support exporting aliases and functions in to the shell, because its works by running through a bash shell and extracting all environment variables from that. It just ignores the aliases and functions. ¹ ² This causes aliases defined in pkgs.mkShell.shellHook not usable in the development shell.

This is also reasonable and wont-fix because direnv is shell-independent while aliases and functions are shell-dependent, as bbenne10 issued here.

A solution when using nix to it is to create a pkgs.writeScriptBin. This is an example I used as an alternative to an alias alias mu="......":

{
  outputs = inputs@{ flake-parts, ... }:
    flake-parts.lib.mkFlake { inherit inputs; } {
      perSystem = { config, self', inputs', pkgs, system, ... }: {
        devShells = {
          default = pkgs.mkShellNoCC {
            packages = with pkgs; [
              lolcat
              (writeShellScriptBin "mu" ''mv $PUBLICEXPORT_SOURCE/publicExport.zip .; unzip -o -q publicExport.zip; rm publicExport.zip'')
            ];
            shellHook = ''
              echo "use mu to extract \$PUBLICEXPORT_SOURCE/publicExport.zip here and remove source." | lolcat
            '';
          };
        };
      };
    };
}