diff --git a/build-constraints.yaml b/build-constraints.yaml
index 1651990d..9aa85cb0 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -2456,6 +2456,9 @@ expected-test-failures:
     # openfile: does not exist
     - skein
 
+    # https://github.com/ekmett/lens/issues/634
+    - lens
+
 # end of expected-test-failures