diff --git a/Dockerfile b/Dockerfile
index 6e3d210..9372b8a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -33,7 +33,7 @@ RUN apt-get update -qq && \
     rm -rf /var/lib/apt/lists /var/cache/apt/archives
 
 # Install application gems
-COPY Gemfile Gemfile.lock ./
+COPY Gemfile Gemfile.lock .ruby-version ./
 RUN bundle install && \
     rm -rf ~/.bundle/ "${BUNDLE_PATH}"/ruby/*/cache "${BUNDLE_PATH}"/ruby/*/bundler/gems/*/.git && \
     bundle exec bootsnap precompile --gemfile