diff --git a/Pipfile b/Pipfile
index 130270bd..710904c0 100644
--- a/Pipfile
+++ b/Pipfile
@@ -7,7 +7,7 @@ sphinx = "<=1.5.5"
 "-e ." = "*"
 twine = "*"
 "sphinx-click" = "*"
-"pytest-xdist" = {version = "*", os_name = '=="posix"'}
+"pytest-xdist" = {version = "*", os_name = "=='posix'"}
 
 
 [requires]