diff --git a/requirements-dev.txt b/requirements-dev.txt
index afc11caf..221b5997 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -27,6 +27,8 @@ autopep8==1.6.0
 grip==4.5.2
 
 # Packaging
+# Used to put together a WiX configuration from template/auto-gen
+lxml==4.6.4
 # We only need py2exe on windows.
 py2exe==0.11.0.1; sys_platform == 'win32'