What Is XP123.com?

Updated

XP123.com is Bill Wake's personal site for essays and resources on Extreme Programming (XP), Agile, Lean, Scrum, and related software development topics. It is best understood as a long-running practitioner library rather than a company or product site: the material is written by one author, aimed at people who want to understand or apply agile and XP practices, and organized around articles, comics, reviews, and links to related resources.

What you'll find on the site

The homepage presents the site as "Exploring Extreme Programming" and describes XP as a form of Agile software development. The content is grouped into several areas:

  • Start Here pages — overviews of specific areas, including Comics, Test-Driven Development (TDD), Refactoring, and User Stories.
  • Most Popular Articles — a curated list that includes "TDD is an Alchemy Trick: Points and Partitions," "INVEST in Good Stories," "Twenty Ways to Split Stories," "XP on One Page," "Scrum on a Page," "Set-Based Concurrent Engineering," "Scrum from Hell," and "Test-First Challenge."
  • Resources — pointers to material on Refactoring, TDD, Set-Based Design, Coaching, and Testing.
  • Reviews — mostly book reviews across a variety of topics. The site notes that buying a book through an author link earns a small Amazon credit.
  • Related Sites — some material has moved elsewhere: billwake.com for posts unrelated to agile software, and jobaids.info for material on creating job aids.

The site also links to a comics series, a Twitch channel with a varying schedule announced on Mastodon, and a current project described as "a breadboard for learning about compilers."

Who runs it

Bill Wake is an independent consultant and teacher who has worked with XP and Agile software for many years across domains including financial, biotechnology, and publishing. He is the author of Extreme Programming Explored, Refactoring Workbook, Design Patterns in Java (with Steve Metsker), and Refactoring in Ruby (with Kevin Rutherford). He can be followed on Mastodon at @[email protected].

When XP123.com is useful to you

  • You want plain-language explanations of XP and agile practices, especially TDD, refactoring, and user stories.
  • You are looking for teaching material or job aids you can adapt for a team.
  • You want a practitioner's reading list on splitting stories, set-based design, or coaching.
  • You are researching the history and vocabulary of XP and Agile as they were discussed in the 1990s and 2000s.

It is less suited to you if you need a commercial tool, a hosted service, or vendor support — the site is a personal collection of essays and references, not a product. The page evidence does not indicate any pricing, login requirement, or paid membership, so treat it as publicly readable editorial content unless you find otherwise on a specific page.