nix-your-shell

A nix and nix-shell wrapper for shells other than bash.

nix develop and nix-shell use bash as the default shell, so nix-your-shell prints shell snippets you can source to use the shell you prefer inside of Nix shells.

Usage

nix-your-shell will print out shell environment code you can source to activate nix-your-shell. For example:

```ShellSession $ nix-your-shell fish

If you see this output, you probably forgot to pipe it into source:

nix-your-shell fish | source

function nix-shell --description "Start an interactive shell based on a Nix expression" nix-your-shell fish nix-shell -- $argv end

function nix --description "Reproducible and declarative configuration management" nix-your-shell fish nix -- $argv end ```

These replace commands like nix foo bar with nix-your-shell fish nix foo bar. nix-your-shell then parses the nix arguments and adds a --command fish argument before launching the underlying command.

Then, nix-shell, nix develop, and nix shell will use your shell instead of bash, unless overridden explicitly with a --command argument.

Fish

Add to your ~/.config/fish/config.fish:

fish if command -q nix-your-shell nix-your-shell fish | source end

Zsh

Add to your ~/.zshrc:

zsh if command -v nix-your-shell > /dev/null; then nix-your-shell zsh | source /dev/stdin fi

Nushell

[!IMPORTANT] Nushell version >=0.83.0 is required

[!NOTE] Nushell requires sourced configuration files to exist before nu is started.

Add to your ~/.config/nushell/config.nu:

nu source nix-your-shell.nu

To generate nix-your-shell.nu file:

Either manually generate it:

sh nix-your-shell nu | save nix-your-shell.nu

Or populate its content through flakes and home-manager:

nix { config, pkgs, ... }: { home.file."${config.xdg.configHome}/nushell/nix-your-shell.nu".source = pkgs.nix-your-shell.generate-config "nu"; }

Installation

You can either install nix-your-shell from this repository or from nixpkgs. The version packaged in nixpkgs will probably lag behind this repository by about a week or so.

nix profile

To install the latest version with nix profile, use one of:

sh nix profile install github:MercuryTechnologies/nix-your-shell nix profile install "nixpkgs#nix-your-shell"

nix-env

To install the latest version with nix-env, use one of:

sh nix-env --install --file https://github.com/MercuryTechnologies/nix-your-shell/archive/refs/heads/main.tar.gz nix-env --install nix-your-shell

You can later remove the installed program with nix-env --uninstall nix-your-shell.

nix run

Run dynamically with nix run:

sh nix run github:MercuryTechnologies/nix-your-shell -- zsh nix run "nixpkgs#nix-your-shell" -- zsh

Note that because the generated shell code will refer to the dynamically-built nix-your-shell executable, it may get garbage collected and cause problems later.

Flakes

nix-your-shell is packaged in nixpkgs, so you can add pkgs.nix-your-shell to environment.systemPackages if you don't need the bleeding edge releases from this repo.

Add to a NixOS flake configuration using the overlay:

flake.nix:

```nix { inputs = { nixpkgs.url = "github:NixOS/nixpkgs"; nix-your-shell = { url = "github:MercuryTechnologies/nix-your-shell"; inputs.nixpkgs.follows = "nixpkgs"; }; };

outputs = { self, nixpkgs, ... } @ attrs: { nixosConfigurations = { YOURHOSTNAME = nixpkgs.lib.nixosSystem { system = "x8664-linux"; specialArgs = attrs; modules = [./YOUR_HOSTNAME.nix]; }; }; }; } ```

./YOUR_HOSTNAME.nix:

```nix { config, pkgs, nix-your-shell, ... }: { nixpkgs.overlays = [ nix-your-shell.overlays.default ];

environment.systemPackages = [ pkgs.nix-your-shell ];

# Example configuration for fish: programs.fish = { enable = true; promptInit = '' nix-your-shell fish | source ''; };

# ... extra configuration } ```

Adding support for new shells

See #23 for an example of adding support for a new shell to nix-your-shell.

Comparison with any-nix-shell

any-nix-shell does roughly the same thing, and serves as the inspiration for nix-your-shell.

There are a few reasons I wrote nix-your-shell as a competitor:

• any-nix-shell doesn't support Nix flakes through nix develop. nix-your-shell does.
• any-nix-shell is a hodgepodge of shell scripts with multiple layers of eval and templating, making hacking or modifying it challenging. In contrast, nix-your-shell is written in Rust with a relatively straightforward structure (the shell environment code generation command and the nix wrappers are the same, so there's no need for dotfile executables on your $PATH).

However, any-nix-shell can optionally display the packages in the current shell on a righthand prompt. nix-your-shell does not support this.