diff --git a/ops/nixos/marukuru/default.nix b/ops/nixos/marukuru/default.nix
index 816ea02c57..1a1ee28402 100644
--- a/ops/nixos/marukuru/default.nix
+++ b/ops/nixos/marukuru/default.nix
@@ -148,6 +148,10 @@ in {
           gitlab_rails['gitlab_email_reply_to'] = 'noreply@hg.lukegb.com'
 
           prometheus['enable'] = false
+
+          puma['min_threads'] = 1
+          puma['max_threads'] = 1
+          puma['worker_processes'] = 0
         '';
       };
     };