diff --git a/build-constraints.yaml b/build-constraints.yaml
index 4a053089..5d5a08dd 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3869,6 +3869,9 @@ expected-test-failures:
     # https://github.com/louispan/data-diverse/issues/3
     - data-diverse
 
+    # https://github.com/Quid2/flat/issues/1
+    - flat
+
 # end of expected-test-failures
 
 # Benchmarks which are known not to build. Note that, currently we do not run