See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1049343

--- a/Rakefile
+++ b/Rakefile
@@ -4,6 +4,9 @@
 # Add your own tasks in files placed in lib/tasks ending in .rake,
 # for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
 
+# See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1049343
+require 'google/protobuf'
+
 Rake::TaskManager.record_task_metadata = true
 
 require File.expand_path('config/application', __dir__)
--- a/config/bundler_setup.rb
+++ b/config/bundler_setup.rb
@@ -22,3 +22,4 @@
 end
 
 require 'bundler/setup'
+require 'google/protobuf'