Command Shell

A shell is a program that translates text commands (like ls, vim, reboot etc) into instructions for your computer. The default shell on NixOS is bash, but it can be easily changed.

Note: Zsh is used here as an example. You can use other shells, eg fish nushell.

Enable

Always enable the shell system-wide, even if it's already enabled in your home.nix. Otherwise it wont source the necessary files.

/etc/nixos/configuration.nix

programs.zsh.enable = true;

Changing default shell

defaultUserShell in the options search

useDefaultShell in the options search

To only change the default shell for one of the users, See

<name>.shell <name>.shell in the options search

Changing /bin/sh

Warning: Please note that NixOS assumes all over the place that shell is Bash, so override the default setting only if you know exactly what you're doing.

/bin/sh is a symlink to your default POSIX-Compliant shell. It's used when writing shell scripts, so that the script works on all machines independently of what shell the user is using. /bin/sh doesn't have to be the same as your interactive shell (e.g. the one you use in your terminal). In fact, a lot of people set their interactive shells to zsh/fish, but set /bin/sh to dash, because it's fast and scripts don't need any of those fancy zsh/fish features.

To change your default POSIX shell on NixOS, use

# Dash is just an example, you can use whatever you want
environment.binsh = "${pkgs.dash}/bin/dash";

See also

• Zsh
• Fish
• Nushell