diff --git a/build-constraints.yaml b/build-constraints.yaml
index 564334a2..55597f2b 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -3870,6 +3870,9 @@ expected-test-failures:
     # https://github.com/Quid2/flat/issues/1
     - flat
 
+    # https://github.com/hpdeifel/hledger-iadd/issues/26
+    - hledger-iadd
+
 # end of expected-test-failures
 
 # Benchmarks which are known not to build. Note that, currently we do not run