diff --git a/src/requirements.txt b/src/requirements.txt
index c0e094c..0c335d9 100644
--- a/src/requirements.txt
+++ b/src/requirements.txt
@@ -33,3 +33,5 @@ python-multipart
 orjson
 argon2-cffi
 toga-core>=0.5.2
+pillow
+toga-dummy>=0.5.2  # for headless GUI tests