diff --git a/docker/development.dockerfile b/docker/development.dockerfile
index 17d6498..ec51911 100644
--- a/docker/development.dockerfile
+++ b/docker/development.dockerfile
@@ -21,6 +21,7 @@ php7-dom \
 php7-json \
 php7-mbstring \
 php7-session \
+php7-xml \
 "
 
 # installation
diff --git a/docker/production.dockerfile b/docker/production.dockerfile
index fb8ed7c..0f8246a 100644
--- a/docker/production.dockerfile
+++ b/docker/production.dockerfile
@@ -23,6 +23,7 @@ php7-dom \
 php7-json \
 php7-mbstring \
 php7-session \
+php7-xml \
 shadow \
 "