diff --git a/requirements.txt b/requirements.txt
index 2fb902e..e60ec41 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,3 @@
-pbr>=1.8
-psutil==3.3.0
-six==1.10.0
-wheel==0.24.0
+pbr>=1.6
+psutil>=1.1.1
+six>=1.9.0