diff --git a/Dockerfile b/Dockerfile
index cb88212..c0ee6c9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -5,5 +5,5 @@ FROM circleci/python
 
 ### Install dependent packages
 RUN sudo pip install awscli ecs-deploy && \
-    sudo apt-get install -y jq gettext && \
+    sudo apt-get install -y jq gettext jsonnet && \
     aws --version