diff --git a/build-constraints.yaml b/build-constraints.yaml
index d4e1acc9..4988765e 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -4687,6 +4687,9 @@ packages:
 
     "Jan Synacek <jan.synacek@scrive.com> @jsynacek":
         - hpqtypes
+        
+    "Daan Leijen <daan@effp.org> @daanx:
+        - isocline
 
     "Grandfathered dependencies":
         - snappy