diff --git a/requirements-dev.in b/requirements-dev.in
index 1005cc1..5d6b9a3 100644
--- a/requirements-dev.in
+++ b/requirements-dev.in
@@ -2,6 +2,8 @@
 
 # Linting and fixing, including isort
 ruff
+# Typing
+pyrefly
 
 # Test suite
 pytest