Extreme Programming (XP) is closely related to agile principles and emphasizes several key values and practices.
- Agility: XP is designed to be adaptive, focusing on frequent iterations and delivering small, functional pieces of software. This ensures continuous feedback and responsiveness to change, which are hallmarks of agile methodologies.
- Trust: XP fosters trust within teams and between teams and stakeholders. It values open communication, shared responsibility, and transparency in development processes.
- Autonomous Teams: Teams in XP are given autonomy to make decisions. The idea is that empowered teams are more productive and can adapt faster to changes. They manage their own work and prioritize tasks collectively.
- Pair Programming: This is one of XP’s core practices. Two developers work together at the same workstation, with one writing code and the other reviewing it in real-time. This promotes better code quality, knowledge sharing, and collective code ownership.
In addition to these, XP also focuses on practices like test-driven development (TDD), **continuous integration**, and refactoring, all aimed at improving software quality and ensuring that the system remains flexible over time.
XP shares much of its philosophy with Agile but is more specific in certain practices, like pair programming and test-driven development.
Extreme Programming (XP) can be used in a Scrum environment, and they are often complementary when combined. XP focuses heavily on technical practices for software development, while Scrum focuses on team organization and the project management framework. Here’s how XP and Scrum can work together:
How XP and Scrum can be combined:
- Scrum for Team Management, XP for Development Practices:
- Scrum provides the structure for team collaboration, setting up sprints, defining roles like Product Owner, Scrum Master, and Development Team, and facilitating ceremonies like daily standups, sprint planning, reviews, and retrospectives.
- XP fills in the gaps on how the development team writes code during those sprints. Practices like pair programming, test-driven development (TDD), continuous integration, and refactoring can be followed as part of the actual implementation work in Scrum.
- Sprints vs. Iterations:
- In Scrum, work is planned in sprints, which typically last 2–4 weeks. In XP, work happens in iterations, which can also follow similar cycles. You can align XP’s iteration cycle with Scrum’s sprint cycle. In this way, the Scrum framework provides the planning and feedback mechanisms, while XP practices ensure high-quality code within that timeframe.
- XP Practices within Scrum: Here’s how XP practices can map onto Scrum:
- Pair Programming: During the sprint, the development team can use pair programming to ensure better code quality and shared knowledge.
- TDD (Test-Driven Development): During sprint execution, teams can use TDD to ensure that code is built with tests first, which aligns with Scrum’s emphasis on delivering potentially shippable product increments.
- Continuous Integration: As teams develop features in a Scrum sprint, they can use continuous integration to ensure that the code is always in a deployable state.
- Collective Code Ownership: In both Scrum and XP, everyone on the team is responsible for the codebase, and this aligns naturally with Scrum’s emphasis on cross-functional teams.
- Retrospectives:
- Both Scrum and XP use retrospectives to continuously improve. In Scrum, this is at the end of each sprint, and in XP, it’s after every iteration. The teams can discuss not only process improvements (Scrum’s focus) but also improvements in development practices (XP’s focus).
Example Process Flow:
- Sprint Planning (Scrum): The Scrum team plans the next sprint, selecting user stories from the product backlog.
- Iteration (XP): During the sprint, the development team applies XP practices like pair programming, TDD, and continuous integration to build the features.
- Daily Scrum/Standup: The team meets daily to ensure progress toward the sprint goal, including progress in using XP practices.
- Sprint Review (Scrum): The team demonstrates the work completed using XP practices and gathers feedback.
- Retrospective (Scrum and XP): The team reflects on both the process (Scrum) and technical practices (XP) to improve for the next sprint.
Underneath an example in ChatGPT
And the library with GPTs (plugins) which can assist XP projects: