diff --git a/requirements.txt b/requirements.txt
index 2eb839af3..3ab40f46a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,8 +1,10 @@
-ansible==2.4.1
+# to avoid dependency conflicts, try to use ranges, eventually banning a
+# buggy minor version (!=) or capping (<) once you have proof it breaks.
+ansible>=2.4.1
 numpy
 elasticsearch
-grafyaml==0.0.7
+grafyaml>=0.0.7
 openstacksdk
-python-dateutil==2.4.2
-python-openstackclient==3.11.0
-pykwalify==1.6.0
+python-dateutil>=2.4.2
+python-openstackclient>=3.11.0
+pykwalify>=1.6.0