diff --git a/build-constraints.yaml b/build-constraints.yaml
index 6a5e5408..a2bd7c04 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3328,7 +3328,7 @@ packages:
         - collect-errors
         - mixed-types-num
         - cdar-mBound
-        # - aern2-mp
+        - aern2-mp
         # - aern2-real
 
     "Bartosz Nitka <niteria@gmail.com> @niteria":