diff --git a/setup.py b/setup.py
index 2e0315b3..5731414c 100644
--- a/setup.py
+++ b/setup.py
@@ -76,6 +76,11 @@ requires = [
     # TODO: remove version cap once we can drop support for python 2.x
     'cornice<5.0',                      # 3.4.2                 4.0.1
 
+    # TODO: remove this cap once deform releases a new version
+    # cf. https://github.com/malthe/chameleon/issues/318
+    # and https://github.com/Pylons/deform/pull/418
+    'Chameleon<3.8.0',                  # 3.7.4
+
     'colander',                         # 1.7.0
     'ColanderAlchemy',                  # 0.3.3
     'deform',                           # 2.0.4