diff --git a/integration/test/Testlib/ModService.hs b/integration/test/Testlib/ModService.hs
index 40338685ec3..7378402cb4d 100644
--- a/integration/test/Testlib/ModService.hs
+++ b/integration/test/Testlib/ModService.hs
@@ -50,7 +50,7 @@ import Prelude
 
 withModifiedBackend :: (HasCallStack) => ServiceOverrides -> ((HasCallStack) => String -> App a) -> App a
 withModifiedBackend overrides k =
-  startDynamicBackends [overrides] (\domains -> k (head domains))
+  startDynamicBackends [overrides] (\[domains] -> k domains)
 
 copyDirectoryRecursively :: FilePath -> FilePath -> IO ()
 copyDirectoryRecursively from to = do