Clan is built on Nix. The clan CLI, every template, and every machine configuration are fetched and evaluated through Nix, so you need it installed on any machine you want to use as a setup machine. direnv is optional for everyday Clan use but required when you work on Clan itself, because it loads the right devshell as soon as you cd into the repository.
If you already run NixOS, you can skip the Nix section. Everything else applies equally.
Install Nix through the official installer:
curl --proto '=https' --tlsv1.2 -sSf -L https://artifacts.nixos.org/nix-installer | sh -s -- install --enable-flakesThis fetches the NixOS installer and runs it. The script sets up /nix, configures the daemon, and turns on the nix-command and flakes experimental features that Clan relies on. Passing --enable-flakes skips the interactive prompt the installer would otherwise show.
Once the installer finishes, open a new shell and confirm the install:
nix --versionYou should see a version string. If the command is not found, restart your terminal so the updated PATH takes effect.
NixOS ships with Nix, so you can skip this section. Make sure experimental-features = nix-command flakes is present in your nix.conf or nix.settings.experimental-features in your NixOS configuration.
direnv watches for an .envrc file in the current directory and loads its environment automatically. In Clan, every devshell is wired up through an .envrc, so direnv makes the right tools appear the moment you enter a directory and disappear when you leave.
Install direnv and its Nix integration through Nix itself:
nix profile add nixpkgs#nix-direnv nixpkgs#direnvnix-direnv is the shim that makes direnv cache Nix devshells, so they only rebuild when inputs change.
Next, hook direnv into your shell. For bash and zsh in one go:
echo 'eval "$(direnv hook zsh)"' >> ~/.zshrc && echo 'eval "$(direnv hook bash)"' >> ~/.bashrc && eval "$SHELL"The eval "$SHELL" at the end restarts your shell so the hook is active immediately.
From now on, every time you cd into a directory that contains an .envrc, direnv will ask you to approve it once:
direnv: error .envrc is blocked. Run `direnv allow` to approve its contentRun direnv allow in that directory and the environment loads. This only needs to happen once per .envrc, and again whenever the file changes.
With Nix installed you are ready to follow the Quick Start or any of the full install guides. If you intend to contribute to Clan itself, continue with the Contributing guide, which relies on direnv to load the development environment.