diff --git a/build-constraints.yaml b/build-constraints.yaml
index ea333df3..dcee9bd1 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1737,6 +1737,7 @@ packages:
 
     "Michael Walker <mike@barrucadu.co.uk> @barrucadu":
         - both
+        - concurrency
         - dpor
         - dejafu
         - async-dejafu