diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 000000000..b844b143d
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1 @@
+Gemfile.lock
diff --git a/.gitignore b/.gitignore
index 3f5f36d8f..ad52e2ec4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,7 @@
 !.rubocop_todo.yml
 !.rubocop.yml
 !.travis.yml
+!.dockerignore
 pkg/*
 doc/*
 Gemfile.lock
diff --git a/Dockerfile b/Dockerfile
index 9929fe691..9621ba4b1 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,9 +1,9 @@
-FROM ruby:2.4.0
+FROM ruby:2.4
 
 RUN mkdir /twilio
 WORKDIR /twilio
 
 COPY . .
 
-RUN bundle install 
+RUN bundle install
 RUN bundle exec rake install