diff --git a/ruby/Gemfile b/ruby/Gemfile
index 70dd9c594c98bf1c61b14a9532ddefa99b5cac19..b2f0a36524ceae9cccc6c9b6d7273ecd2cb9ea10 100644
--- a/ruby/Gemfile
+++ b/ruby/Gemfile
@@ -10,6 +10,7 @@ gem 'gitlab-gollum-rugged_adapter', '~> 0.4.4.4.gitlab.1', require: false
 gem 'grpc', '~> 1.42.0' # keep in lock-step with grpc-tools
 gem 'sentry-raven', '~> 3.0', require: false
 gem 'faraday', '~> 1.0'
+gem 'rouge', '~> 3.27.0'
 gem 'rbtrace', require: false
 
 # Labkit provides observability functionality
diff --git a/ruby/Gemfile.lock b/ruby/Gemfile.lock
index fd0dea027e0dbf2e8b9130a9e69a9523fdcd6fc6..6e9f68b27723356877152a871a567ed0416079bc 100644
--- a/ruby/Gemfile.lock
+++ b/ruby/Gemfile.lock
@@ -241,6 +241,7 @@ DEPENDENCIES
   pry (~> 0.12.2)
   rbtrace
   rdoc (~> 6.0)
+  rouge (~> 3.27.0)
   rspec
   rspec-parameterized
   rubocop (~> 0.69)