diff --git a/virt.yaml b/virt.yaml
index cec0401..1b45663 100644
--- a/virt.yaml
+++ b/virt.yaml
@@ -35,6 +35,10 @@ data:
     - ocaml-libnbd-devel
     - qemu-kvm-tests
     - qemu-kvm-tests-debuginfo
+  buildopts:
+    rpms:
+      macros: |
+        %_smp_ncpus_max 16
   components:
     rpms:
       SLOF: