The three key figures behind GitHub's development, PJ Hyett, Tom Preston-Werner, and Chris Wanstrath, have each contributed significantly to the platform's features and infrastructure. PJ Hyett, known for his work on Err the Blog and co-creating FamSpam, focuses on GitHub's Gems and service integration while enjoying rewriting its infrastructure in bash. Tom Preston-Werner, the creator of Gravatar and author of RubyGems such as Chronic and God, manages GitHub's UI and utilizes Erlang for code rewriting. Chris Wanstrath, a fan of JavaScript, brutalist architecture, and shabu-shabu, is also instrumental in GitHub's development and is open to communication via email.