add remote builder for hs

os/builder.nix

@@ -0,0 +1,19 @@
+{ config, pkgs, ... }: 
+let sshKeys = with (import ../sshKeys.nix); [
+  hs
+];
+in
+{
+  users.users.remotebuild = {
+    isNormalUser = true;
+    createHome = false;
+    group = "remotebuild";
+    shell = pkgs.bash;
+
+    openssh.authorizedKeys.keys = sshKeys;
+  };
+
+  users.groups.remotebuild = {};
+
+  nix.settings.extra-trusted-users = [ "remotebuild" ];
+}