diff --git a/build-constraints.yaml b/build-constraints.yaml
index 1252a8f1..8a72b21e 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -5212,7 +5212,6 @@ packages:
         - rainbow < 0 # via lens-simple
         - rainbox < 0 # via lens-simple
         - polysemy < 0 # via loopbreaker
-        - mmark-ext < 0 # via modern-uri
         - witherable < 0 # via monoidal-containers
         - msgpack-aeson < 0 # via msgpack
         - mysql-haskell-nem < 0 # via mysql-haskell