distributed builds

hosts/citadel/default.nix

@@ -57,6 +57,9 @@ in {
     ../common/optional/gaming.nix
     ../common/optional/powersave.nix
     ../common/optional/restic-backup.nix
+
+    # This machine is used for remote building
+    ../common/optional/distributed_builds/remote-builder-machine.nix
   ];
 
   boot = {

hosts/common/optional/distributed_builds/local-machine.nix

@@ -0,0 +1,7 @@
+{
+  secrets = {
+    "ssh_keys/root/remotebuild" = {
+      path = "/root/.ssh/remotebuild";
+    };
+  };
+}

hosts/common/optional/distributed_builds/remote-builder-machine.nix

@@ -0,0 +1,18 @@
+{
+  secrets = {
+    "ssh_keys/root/remotebuild.pub" = {
+      path = "/root/.ssh/remotebuild.pub";
+    };
+  };
+  users.users.remotebuild = {
+    isNormalUser = true;
+    createHome = false;
+    group = "remotebuild";
+
+    openssh.authorizedKeys.keyFiles = [/root/.ssh/remotebuild.pub];
+  };
+
+  users.groups.remotebuild = {};
+
+  nix.settings.trusted-users = ["remotebuild"];
+}

hosts/semita/default.nix

@@ -18,7 +18,6 @@
   pieholeIp = configVars.networking.addresses.piehole.ip;
   gatewayIp = configVars.networking.addresses.gateway.ip;
   semitaIp = configVars.networking.addresses.semita.ip;
-
 in {
   imports = [
     # Create users for this host
@@ -84,6 +83,25 @@ in {
     };
   };
 
+  nix.distributedBuilds = true;
+  nix.buildMachines = [
+    {
+      hostName = "builder";
+      systems = ["x86_64-linux"];
+      maxJobs = 8;
+      speedFactor = 2;
+      supportedFeatures = ["nixos-test" "benchmark" "big-parallel" "kvm"];
+    }
+  ];
+  programs.ssh.extraConfig = ''
+    Host builder
+      HostName 192.10.99.14
+      Port 2222
+      User builder
+      IdentitiesOnly yes
+      IdentityFile /root/.ssh/id_builder
+  '';
+
   environment.variables = {
     GDK_SCALE = "2";
     GDK_DPI_SCALE = "0.6";
@@ -96,10 +114,12 @@ in {
     pkgs.sof-firmware
   ];
 
-  swapDevices = [ {
+  swapDevices = [
+    {
       device = "/.swapvol/swapfile";
-     size = 32*1024;
+      size = 32 * 1024;
-   } ];
+    }
+  ];
 
   # Add hardware support for intel gpus as specified here: https://nixos.wiki/wiki/Jellyfin
   nixpkgs.config.packageOverrides = pkgs: {