diff --git a/requirements-test.txt b/requirements-test.txt
index a46c4f3..5ad6c45 100644
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,7 +1,7 @@
 pytest
 pytest-trio
 pdbpp
-mypy
+mypy<0.920
 trio_typing
 pexpect
-towncrier
\ No newline at end of file
+towncrier