-pbr!=2.1.0,>=2.0.0 # Apache-2.0
-PyYAML>=3.10.0 # MIT
-GitPython>=1.0.1 # BSD License (3 clause)
-keystoneauth1>=3.1.0 # Apache-2.0
-python-cinderclient>=3.1.0 # Apache-2.0
-python-glanceclient>=2.8.0 # Apache-2.0
-python-heatclient>=1.6.1 # Apache-2.0
-python-keystoneclient>=3.8.0 # Apache-2.0
-python-neutronclient>=6.3.0 # Apache-2.0
-python-novaclient>=9.0.0 # Apache-2.0
-requests>=2.14.2 # Apache-2.0
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+pbr!=2.1.0 # Apache-2.0
+PyYAML # MIT
+requests # Apache-2.0