diff --git a/Pipfile b/Pipfile
index 34164d5..c033715 100644
--- a/Pipfile
+++ b/Pipfile
@@ -8,6 +8,6 @@ flake8 = "*"
 twine = "*"
 
 [packages]
-requests = ">=2.21.0"
-future = ">=0.18.2"
-ujson = ">=2.0.3"
+requests = "~=2.21.0"
+future = "~=0.18.2"
+ujson = "~=2.0.3"