During November 2025, Paul Arndt focused on backend stability for the rubygems/rubygems and ruby/ruby repositories, addressing reliability issues in gem cache maintenance. He implemented robust error handling in Ruby and Ruby on Rails, specifically rescuing Errno::ENOENT during gem cache file deletions to prevent crashes when files were missing. This approach allowed cache maintenance processes to continue uninterrupted, even in concurrent environments where files might disappear unexpectedly. By propagating these changes across both repositories and collaborating with other maintainers, Paul improved cross-repo consistency and reduced support overhead, ultimately enhancing the resilience of gem tooling for the broader Ruby ecosystem.