Explore the evolution and relevance of eXtreme Programming (XP) in the 21st century through this insightful conference talk by Rachel Davies at GOTO London 2015. Trace the journey of XP from its radical beginnings to its current state, examining how it compares to mainstream Agile approaches like Scrum. Discover how XP practices have adapted to modern software development, including continuous integration, pair programming, and mob programming. Learn about the benefits of XP, including deeper aspects like mastery and autonomy. Gain valuable insights into how XP can bring together various development methodologies, from DevOps to Lean Startup, and understand its potential to address "Agile sadness" in today's software development landscape.