extreme programming (XP)

XP

agille software development framework noted for its heavy emphasis on software engineering practices. it aims to create a higher quality of life for the developer and better software for the customer. belives in the 40 workweek alongside frequent releases and customer centricity. empjasis on simplicity

X P values

communication, simplicity, feedback, respect, courage

customer

decides which features are needed eventually and which are needed next. when the customer is thousands of users, team select one or more customer proxies to represent the voice of the customer

tracker

captures metrics, measures progress, and looks for improvement opportunities. it usually a part time role for a team member

coach

mentors team members on how to use XP practices. it’s usually somebody outside the team who has experience in XP

pair programming

two software engineers work side by side to create code at once. each line of code has two people working on it. typically one person writes code, while second person 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, developers are less likely to run the test. it also drives other good practices, such as writing clean tests and automating testing and integrations

continous integration

merge local code onto the main repository regularly, at least a few times a day. frequent integration reduces conflicts and allows automatic builds and tests to run

test first programming

traditional software development writes and passes tests after development, but XP takes the opposite approach. also called test driven development (TDD), this writes tests and then writes the code to pass the tests

slack

a team’s weekly plan should not be filled to capacity. see certmaster for more XPpractices

strengths of XP

hgihly efficient, builds the most essential increments first, and does not waste time on low prioruty features. continous integration automation, and a high rate of adaptability are built into the process. teams using XP come together quickly and experience less project failure because the customer is a team member

XP weaknesses

has limited use outside the scope of building good software. code centric practices can result in a lackluster design, which may drive away customers. the rapid pace of work can cause stress, and minimal documentation can hinder new team members’ understanding. the framework also relies on face to face interaction between team members and customers

use cases

• small collocated teams who must manage changing and unknown requirements

• projects with tight deadlines

• teams with test automation capabilities