https://duan.ca/tag/nixpkgs/ <p>So, you use a standalone home-manager, it's set up with flake, tracking a particular nixpkgs channel. How do you use a package from another channel? This seemingly simple task took me, a Nix noob, quite a bit of research to solve. Here's how I did it.</p> <p>A simple flake.nix for home-manager might look like this:</p> <pre><code class="language-nix">{ inputs = { nixpkgs.url = &quot;github:nixos/nixpkgs/nixos-21.11&quot;; home-manager.url = &quot;github:nix-community/home-manager/release-21.11&quot;; home-manager.inputs.nixpkgs.follows = &quot;nixpkgs&quot;; }; outputs = { self, nixpkgs, home-manager }: { &quot;dan@some-mac&quot; = home-manager.lib.homeManagerConfiguration { username = &quot;dan&quot;; system = &quot;x86_64-darwin&quot;; homeDirectory = &quot;/home/dan&quot;; configuration = { config, pkgs ... }: { home.packages = [ pkgs.hello ]; }; }; }; } </code></pre> <p>A few things of note:</p> <ol> <li>home manager is set to follow <code>nixpkgs</code>, which tracks <code>nixos-21.11</code>.</li> <li><code>pkgs.hello</code> refers to the package in <code>nixos-21.11</code> as well.</li> </ol> <p>To put things in concrete terms, our goal is to put a package from a channel other than <code>nixos-21.11</code> alongside <code>pkgs.hello</code>.</p> <p>The key to my solution is the <code>extraModules</code> in <code>home-manager.lib.homeManagerConfiguration</code>'s argument set. We'll leverage it to modify the environment made available to its sibling, <code>configuration</code>.</p> <p>First, add the new channel as input <code>nixpkgs-unstable</code>:</p> <pre><code class="language-nix">{ inputs = { # ... nixpkgs-unstable.url = &quot;github:nixos/nixpkgs&quot;; }; ... } </code></pre> <p>Then, add a small module to <code>extraModules</code>. In it we make <code>nixpkgs-unstable</code> an argument to <code>_module</code>.</p> <pre><code class="language-nix">{ input = { ... }; outputs = { self, nixpkgs, nixpkgs-unstable, home-manager }: { # Note we also pass in nixpkgs-unstable here &quot;dan@some-mac&quot; = home-manager.lib.homeManagerConfiguration { extraModules = [ ({ pkgs, ... }: rec { _module.args.nixpkgs-unstable = import nixpkgs-unstable { inherit system; }; }) ]; # ... }; }; } </code></pre> <p>... now that we added <code>args.nixpkgs-unstable</code>, it becomes available in the configuration:</p> <pre><code class="language-nix">{ input = { ... }; outputs = { self, nixpkgs, nixpkgs-unstable, home-manager }: { # Note we also pass in nixpkgs-unstable here &quot;dan@some-mac&quot; = home-manager.lib.homeManagerConfiguration { # ... configuration = { config, pkgs, nixpkgs-unstable, ... }: home.packages = [ pkgs.hello nixpkgs-unstable.python39Packages.python-lsp-server ]; }; }; }; } </code></pre> <p>There, we made <code>python39Packages.python-lsp-server</code> from nixpkgs's master branch appear alongside our standard, default channel.</p> <p>And that's how you add packages from a different channel in a flake setup for standalone home-manager.</p> Tue, 15 Mar 2022 18:53:59 -0700 https://duan.ca/2022/03/15/standalone-home-manager-flake-channels/ https://duan.ca/2022/03/15/standalone-home-manager-flake-channels/