This page describes how to build and install arbitrary packages from source on a NixOS fleet using nixa.

I have a repo golang-samples that contains a file context_channel.go. We will build and install this system-wide as golang-samples.

Under nixa/modules, i’ve created golang-samples.nix:

{ pkgs, ... }: {
  environment.systemPackages = with pkgs; [
    (stdenv.mkDerivation {
      name = "golang-samples";
      src = fetchFromGitHub {
        owner = "nihr43";
        repo = "golang-samples";
        rev = "cdf9462";
        sha256 = "sha256-Z6Iot+xI1y85BQOC8ipDQEJUXKoilDBrrSBfJ7jybzI=";
      };
      nativeBuildInputs = [ go ];
      buildPhase = ''
        export GOCACHE=$TMPDIR/go-cache
        mkdir -p $GOCACHE
        go build -mod=vendor -o golang-samples context_channel.go
      '';
      installPhase = ''
        mkdir -p $out/bin
        cp golang-samples $out/bin/
      '';
    })
  ];
}

environment.systemPackages is indeed allowed to be defined in multiple .nix files; the lists will be concatinated.

In my inventory, we simply add this module to a host group:

lanner:
  hosts:
    10.0.0.1:
      hostname: lanner-c8f0
      stateversion: 24.11
      loopback: 10.0.0.1
      as_number: 65501
      bgp_interfaces:
        - enp2s0f0
        - enp2s0f1
        - enp2s0f2
        - enp2s0f3
        - enp6s0f0
        - enp6s0f1
        - enp8s0f0
        - enp8s0f1
      bridge_address: 172.30.191.1
  modules:
    - grub_sda_common.nix
    - bgp.nix
    - serial.nix
    - golang-samples.nix
  nix-channel: nixos-24.11

and after applying, the program is available:

nixa > nix-shell --run 'python3 nixa --limit lanner'
10.0.0.1 is reachable
applying modules ['grub_sda_common.nix', 'bgp.nix', 'serial.nix', 'golang-samples.nix'] to lanner: ['10.0.0.1']
10.0.0.1:
---

+++

@@ -8,5 +8,7 @@


     ./serial.nix

+    ./golang-samples.nix
+
   ];
 }
rebuilding NixOS on 10.0.0.1

[root@lanner-c8f0:~]# golang-samples
tick
tock
tick
^C

Do that with ansible!