2 files changed, 30 insertions, 2 deletions
diff --git a/modules/system/activation-checks.nix b/modules/system/activation-checks.nix
new file mode 100644
index 0000000..3f07cb0
--- /dev/null
+++ b/modules/system/activation-checks.nix
@@ -0,0 +1,28 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  buildUsers = optionalString config.services.nix-daemon.enable ''
+    buildUser=$(dscl . -read /Groups/nixbld GroupMembership 2>&1 | awk '/^GroupMembership: / {print $2}')
+    if [ -z $buildUser ]; then
+        echo "Using the nix-daemon requires build users, aborting activation" >&2
+        exit 2
+    fi
+  '';
+in
+
+{
+  options = {
+  };
+
+  config = {
+
+    system.activationScripts.checks.text = ''
+      set +e
+      ${buildUsers}
+      set -e
+    '';
+
+  };
+}
diff --git a/modules/system/activation-scripts.nix b/modules/system/activation-scripts.nix
index aa97633..48d2773 100644
--- a/modules/system/activation-scripts.nix
+++ b/modules/system/activation-scripts.nix
@@ -52,9 +52,7 @@ in
 
       ${cfg.activationScripts.extraActivation.text}
 
-      ${cfg.activationScripts.nix-daemon.text}
       ${cfg.activationScripts.nix.text}
-
       ${cfg.activationScripts.accessibility.text}
       ${cfg.activationScripts.applications.text}
       ${cfg.activationScripts.etc.text}
@@ -88,6 +86,8 @@ in
       # Ensure a consistent umask.
       umask 0022
 
+      ${cfg.activationScripts.checks.text}
+
       ${cfg.activationScripts.extraUserActivation.text}
 
       ${cfg.activationScripts.defaults.text}