continuous integration

Continuous integration (CI) is a software engineering practice in which isolated changes are immediately tested and reported on when they are added to a larger code base. The goal of CI is to provide rapid feedback so that if a defect is introduced into the code base, it can be identified and corrected as soon as possible. Continuous integration software tools can be used to automate the testing and build a document trail.

Continuous integration has evolved since its conception. Originally, a daily build was the standard. Now, the usual rule is for each team member to submit work on a daily (or more frequent) basis and for a build to be conducted with each significant change. When used properly, continuous integration provides various benefits, such as constant feedback on the status of the software. Because CI detects deficiencies early on in development, defects are typically smaller, less complex and easier to resolve.

According to Paul Duvall, co-author of Continuous Integration: Improving Software Quality and Reducing Risk, best practices of CI include:

• Committing code frequently.
• Categorizing developer tests.
• Using a dedicated integration build machine.
• Using continuous feedback mechanisms.
• Staging builds.

CI originated from within the Extreme Programming paradigm but the principles can be applied to any iterative programming model, such as agile programming. Traditional development approaches, such as the waterfall model can benefit from using CI methods for the construction stage.

Read more about continuous integration: - On SearchSoftwareQuality.com, Paul Duvall describes the benefits of continuous integration. - Justin Gehtland explains continuous integration. - 'Continuous Integration: Improving Software Quality and Reducing Risk' is available from Amazon.com. - Integratebutton.com is an extension of the book. - MartinFowler.com offers a selection of articles about continuous integration.

Do you have something to add to this definition? Let us know. Send your comments to techterms@whatis.com

Digg This!     StumbleUpon     Del.icio.us

RELATED CONTENT Clean Code: A Handbook of Agile Software Craftsmanship, Chapter 1 -- What Is Clean Code? Agile software development calls on developers to write clean code, according to Robert "Uncle Bob" Martin. This free chapter introduces the concepts... Software development groups take many routes to Agile More software development groups are implementing Agile methodologies, but their routes to adoption are far from straight and narrow and vary from... Agile Software Development: The Cooperative Game, 2nd Edition -- Chapter 3, Communicating, Cooperating Teams Software project teams switching to an agile methodology will find a great resource in this free chapter. XP, Crystal and other agile methodologies...

RELATED GLOSSARY TERMS Terms from Whatis.com − the technology online dictionary Extreme Programming  (SearchSoftwareQuality.com) Extreme Programming (XP) is a pragmatic approach to program development that emphasizes business results first and takes an incremental,... JUnit  (SearchSoftwareQuality.com) JUnit is an open source framework designed for the purpose of writing and running tests in the Java programming language... (Continued)