diff --git a/lnt/testing/profile/perf.py b/lnt/testing/profile/perf.py
--- a/lnt/testing/profile/perf.py
+++ b/lnt/testing/profile/perf.py
@@ -7,7 +7,7 @@
 import traceback
 
 try:
-    from . import cPerf
+    from . import cPerf  # type: ignore  # mypy cannot process Cython modules
 except Exception:
     pass