diff --git a/ops/nixos/whitby/default.nix b/ops/nixos/whitby/default.nix
index 37bf2eb37..5d382d6bf 100644
--- a/ops/nixos/whitby/default.nix
+++ b/ops/nixos/whitby/default.nix
@@ -148,6 +148,7 @@ in lib.fix(self: {
   time.timeZone = "UTC";
 
   nix = {
+    nrBuildUsers = 128;
     maxJobs = lib.mkDefault 64;
     extraOptions = ''
       secret-key-files = /etc/secrets/nix-cache-privkey