diff --git a/clever/requirements.txt b/clever/requirements.txt
index 579c0031..10daf5e1 100644
--- a/clever/requirements.txt
+++ b/clever/requirements.txt
@@ -1,3 +1,4 @@
 flask==0.12.2
 geopy==1.11.0
+lxml==4.2.5
 pymavlink==2.2.10