Extreme Programming

Last updated Apr 3, 2023

• Sapling
• Project

• An Agile Approach for software development
• Heavy emphasis on software engineering practices
• XP takes good software development practices to extreme levels and codifies them
• Puts a customer on the development team
• Aims to create a higher quality of life for the developer and better software for the customer

• Communication
• Simplicity
• Feedback
• Respect
• Courage

• Customer
  • Decides which features are needed eventually and which are needed next
  • Teams can select one of more customer proxies if the “customer” is a large user-base
• Tracker
  • Captures metrics, measures progress, and looks for improvement opportunities
  • Usually part-time role for a team member
• Coach
  • Mentors team members on how to use XP practices. Usually somebody outside the team who has experience in XP

• Pair Programming
  • Two software engineers work side by side to create code at once
  • Typically one person writes the code, while the other watches and provides feedback
• Ten-minute build
  • It should take ten minutes or less to build, test, and deploy the entire system
  • If it takes longer, devs are less likely to run tests
• Continuous Integration
  • Merge local code onto the main repo regularly, at least a few times a day
  • Reduces conflicts and allows automatic builds and tests to run
• Test-first programming
  • traditional software development writes and passes tests after development, but XP does it before
  • Also called “Test Driven Development”
  • Writes tests and then writes the code to pass the tests
• Incremental Design
  • XP adopts incremental design, like all other Agile Approaches
  • Small, infrequent improvements are more valuable than delayed releases
• Sit together
  • Teams work in a shared, open space
• Whole Team
  • Everybody needed for a project is on the team
• On-site Customer
  • XP includes the customer on the team
• Energized Work
  • 40 hour workweeks, max
  • No back to back overtime
• Stories
  • An effective format for communicating requirements
  • User’s needs are written in a short, descriptive format that conveys what the user wants and how it would help them
• Weekly Cycle
  • Similar to a sprint cadence
  • Each week the team selects stories and plans work for the week
• Quarterly Cycle
  • A planning and reflection event
  • Team inspects and adapts their processes
  • Identify major themes for the project and create stories to deliver upon them
• Slack
  • Slack must be built into the team’s weekly plan by including option tasks that the team can reschedule if they don’t have time to complete them

• Strengths
  • Highly efficient
  • Builds the most essential increments first
  • Does not waste time on low-priority features
  • Continuous integration, automation, and a high rate of adaptability
  • Teams come together quickly
  • Less project failure because customer is a team member
• Weaknesses
  • Limited to software development
  • Can result in lackluster design
  • Rapid pace can cause high stress on devs
  • Minimal documentation can hinder new team members’ understanding
  • Relies on face-to-face interaction between team members and customers