diff --git a/buildout.cfg b/buildout.cfg
index 425fe6c..564a0a3 100644
--- a/buildout.cfg
+++ b/buildout.cfg
@@ -7,6 +7,12 @@ recipe = zc.recipe.testrunner
 eggs = zope.sqlalchemy [test]
 defaults = ['--auto-color', '-s', 'zope.sqlalchemy']
 
+[versions:python27]
+configparser = < 5
+contextlib2 = < 21
+importlib-metadata = < 3
+zipp = < 2
+
 [scripts]
 recipe = zc.recipe.egg
 eggs =