1. 1 March Extreme programming

2. Presentations Tuesday Campus Tour Sami Says Hawks Thursday Read2Me UNCSET Oral Lab NetVis If helpful, invite your client

3. Software Engineering Elaborated Steps Concept Requirements Architecture Design Implementation Extreme Programming Unit test Integration System test Maintenance

4. What it is Complete development process First code drop is 2-3 weeks after start Customer a part of the development team Iterative development to the max Derive requirements with customer through hands-on experimentation Agile methodology

5. XP Bills of Rights Developer has a right to Clear requirements and priorities Determine how long a requirement will take to implement Revise estimates Always produce quality code Customer has a right to An overall plan See progress in a running system Change requirements and priorities Be informed of changes to schedule and have input as to how to adapt Cancel in the middle and still have something to show for the investment

6. XP Bills of Rights Developer has a right to Clear requirements and priorities Determine how long a requirement will take to implement Revise estimates Always produce quality code Customer has a right to An overall plan See progress in a running system Change requirements and priorities Be informed of changes to schedule and have input as to how to adapt Cancel in the middle and still have something to show for the investment

7. XP Value System Communication Focus on people, not documentation Simplicity Of process and code Feedback Mechanism to make useful progress Courage To trust in people

8. People Most important factor in the quality of software is the quality of the programmers If your life depended on a particular piece of software, what would you want to know about it? Bollinger (2001): that the person who wrote it was “both highly intelligent and possessed by an extremely rigorous, almost fanatical desire to make their program work the way it should.”

9. Knowledge Workers … prefer closed offices but communicate better in open ones congregate in particular geographical areas move around in the course of their work collaborate concentrate work in the office communicate with people who are close by don't care about facilities gewgaws Davenport, Why Office Design Matters 2005Why Office Design Matters

10. Fundamental Conflict Solutions?

11. Extreme Programming Project http://www.extremeprogramming.org/

12. User Stories Use cases Written by customer Used for planning Developers estimate by story Stories basis for iteration Used to build acceptance tests Remember that correctness equals meeting requirements

13. System Metaphor Initial system design About the level that you’re producing

14. Spikes Technology explorations Focus on high risk items Typically considered throw-away code If not, needs to be agreed to by the whole team

15. Release Planning Focused on iterations Can be defined by function or date Other is adjusted accordingly (Actually four parameters: resources and quality are the other two that can be used to adjust) Planning adapts as the project progresses Project velocity is measured for each iteration Next iteration looks at planned vs. actual time and adjusts accordingly Each iteration has its own plan Developed at the beginning of the iteration

16. Iteration Scope of an iteration Should cover all parts of the system Only add the functions that you need for the current user story or stories Recommendation: 3 weeks Moving people around Backup and training Code is owned by the whole team Pair programming Re-factoring

17. Egoless Programming Weinberg 1971, The Psychology of Computer Programming During the “cowboy” era Observed that programmers needed to be team players Accept inspections and reviews Open to corrections and critiques Ten Commandments (Lamont Adams) Ten Commandments But pride of ownership is critical to quality

18. Pair Programming Two people working at a single computer Built-in backup and inspections Collaboration builds better code Mechanical model One drives, the other talks Keyboard slides between the two Logical model One tactical, the other strategic Both think about the full spectrum but bring different perspectives

19. Pair Programming Experiments Typical numbers show the total manpower consumed not very different Numbers range, but no more than ¼ additional manpower Implication: actual time is reduced Improved satisfaction also improves productivity Williams et al, “Strengthening the Case for Pair-Programming”Strengthening the Case for Pair-Programming

20. Re-factoring Each iteration adds just the function needed If you continue to add new functions every two weeks, code can get messy Re-factoring is the cleaning up of the code at the end of the iteration Critical to maintaining quality code (Also applies to the design)

21. Coding Rules The customer is always available. Code must be written to agreed standards. Code the unit test first. All production code is pair programmed. Only one pair integrates code at a time. Integrate often. Use collective code ownership. Leave optimization till last. No overtime.

22. Communications Avoid unnecessary meeting Daily stand-up meetings In a circle No chairs Everyone must attend Minimizes other meetings Primarily informal as needed

23. When to Use XP Types of projects High risk Poorly understood requirements Team Small size: 2 to 12 Needs to include customer Automated testing Timing issue

24. What Makes a Project XP Paradigm - see change as the norm, not the exception, and optimize for change Values - honor the four values- communication, simplicity, feedback, and courage- in your actions Power sharing - business makes business decisions and development makes technical decisions Distributed responsibility and authority - people get to make the commitments for which they will be held accountable Optimizing process - you are aware of your software development process and when it is working and when it isn't, you are experimenting to fix the parts that aren't working, and you consciously acculturate new team members Ward Cunningham, Ron Jeffries, Martin Fowler, Kent Beck

25. References Agile Methodologies www.martinfowler.com/articles/newMethodology.html www.martinfowler.com/articles/newMethodology.html Discussion http://xp.c2.com/ExtremeProgrammingRoadmap.html http://xp.c2.com/ExtremeProgrammingRoadmap.html