To install the latest development version to the user profile, use the following command:

nix-env -if https://github.com/zhaofengli/colmena/tarball/main

To install the latest stable version, read the corresponding Manual for instructions.

Unstable Binary Cache

A public binary cache is available at https://colmena.cachix.org, courtesy of Cachix. This binary cache contains unstable versions of Colmena built by GitHub Actions.

Basic Configuration

If you use Nix Flakes, follow the Flake version here.

Colmena should work with your existing NixOps and morph configurations with minimal modification (see Migrating from NixOps/morph).

Here is a sample hive.nix with two nodes, with some common configurations applied to both nodes:

  meta = {
    # Override to pin the Nixpkgs version (recommended). This option
    # accepts one of the following:
    # - A path to a Nixpkgs checkout
    # - The Nixpkgs lambda (e.g., import <nixpkgs>)
    # - An initialized Nixpkgs attribute set
    nixpkgs = <nixpkgs>;

    # You can also override Nixpkgs by node!
    nodeNixpkgs = {
      node-b = ./another-nixos-checkout;

    # If your Colmena host has nix configured to allow for remote builds
    # (for nix-daemon, your user being included in trusted-users)
    # you can set a machines file that will be passed to the underlying
    # nix-store command during derivation realization as a builders option.
    # For example, if you support multiple orginizations each with their own
    # build machine(s) you can ensure that builds only take place on your
    # local machine and/or the machines specified in this file.
    # machinesFile = ./machines.client-a;

  defaults = { pkgs, ... }: {
    # This module will be imported by all hosts
    environment.systemPackages = with pkgs; [
      vim wget curl

    # By default, Colmena will replace unknown remote profile
    # (unknown means the profile isn't in the nix store on the
    # host running Colmena) during apply (with the default goal,
    # boot, and switch).
    # If you share a hive with others, or use multiple machines,
    # and are not careful to always commit/push/pull changes
    # you can accidentaly overwrite a remote profile so in those
    # scenarios you might want to change this default to false.
    # deployment.replaceUnknownProfiles = true;

  host-a = { name, nodes, ... }: {
    # The name and nodes parameters are supported in Colmena,
    # allowing you to reference configurations in other nodes.
    networking.hostName = name;
    time.timeZone = nodes.host-b.config.time.timeZone;

    boot.loader.grub.device = "/dev/sda";
    fileSystems."/" = {
      device = "/dev/sda1";
      fsType = "ext4";

  host-b = {
    # Like NixOps and Morph, Colmena will attempt to connect to
    # the remote host using the attribute name by default. You
    # can override it like:
    deployment.targetHost = "host-b.mydomain.tld";

    # It's also possible to override the target SSH port.
    # For further customization, use the SSH_CONFIG_FILE
    # environment variable to specify a ssh_config file.
    deployment.targetPort = 1234;

    # Override the default for this target host
    deployment.replaceUnknownProfiles = false;

    # You can filter hosts by tags with --on @tag-a,@tag-b.
    # In this example, you can deploy to hosts with the "web" tag using:
    #    colmena apply --on @web
    # You can use globs in tag matching as well:
    #    colmena apply --on '@infra-*'
    deployment.tags = [ "web" "infra-lax" ];

    time.timeZone = "America/Los_Angeles";

    boot.loader.grub.device = "/dev/sda";
    fileSystems."/" = {
      device = "/dev/sda1";
      fsType = "ext4";

The full set of deployment options can be found here.

Now you are ready to use Colmena! To build the configuration:

colmena build

To build and deploy to all nodes:

colmena apply

Next Steps

  • Head to the Features section to see what else Colmena can do.
  • Read more about options available in Colmena in the Reference section.