Continuous delivery - wikipedia Continuous delivery Continuous delivery ( CD ) is a software engineering approach in which teams produce software in short cycles, ensuring that the software can be reliably released at any time. It aims at building, testing, and releasing software faster and more frequently. The approach helps reduce the cost, time, and risk of delivering changes by allowing for more incremental updates to applications in production. A straightforward and repeatable deployment process is important for continuous delivery. Contents 1 Relationship to DevOps 2 Relationship to continuous deployment 3 Principles 4 Deployment pipeline 5 Tools / tool types 6 Architecting for continuous delivery 7 Implementation and usage 8 Benefits and obstacles 9 Strategies to overcome adoption challenges 10 See also 11 Further reading 12 References Relationship to DevOps Continuous delivery and DevOps are similar in their meanings and are often conflated, but they are two different concepts. DevOps has a broader scope, and centers around the cultural change, specifically the collaboration of the various teams involved in software delivery ( developers, operations, quality assurance, management, etc. ), as well as automating the processes in software delivery. Continuous delivery, on the other hand, is an approach to automate the delivery aspect, and focuses on bringing together different processes and executing them more quickly and more frequently. Thus, DevOps can be a product of continuous delivery, and CD flows directly into DevOps. Relationship to continuous deployment Continuous delivery is sometimes confused with continuous deployment. Continuous deployment means that every change is automatically deployed to production. Continuous delivery means that the team ensures every change can be deployed to production but may choose not to do it, usually due to business reasons. In order to do continuous deployment one must be doing continuous delivery. Principles Continuous delivery treats the commonplace notion of a deployment pipeline as a lean Poka - Yoke : a set of validations through which a piece of software must pass on its way to release. Code is compiled if necessary and then packaged by a build server every time a change is committed to a source control repository, then tested by a number of different techniques ( possibly including manual testing ) before it can be marked as releasable. Developers used to a long cycle time may need to change their mindset when working in a CD environment. It is important to understand that any code commit may be released to customers at any point. Patterns such as feature toggles can be very useful for committing code early which is not yet ready for use by end users. Using NoSQL can eliminate the step of data migrations and schema changes, often manual steps or exceptions to a continuous delivery workflow. Other useful techniques for developing code in isolation such as code branching are not obsolete in a CD world, but must be adapted to fit the principles of CD - for example, running multiple long - lived code branches can prove impractical, as a releasable artifact must be built early in the CD process from a single code branch if it is to pass through all phases of the pipeline. Deployment pipeline Continuous delivery is enabled through the deployment pipeline. The purpose of the deployment pipeline has three components : visibility, feedback, and continually deploy. Visibility -- All aspects of the delivery system including building, deploying, testing, and releasing are visible to every member of the team to promote collaboration. Feedback -- Team members learn of problems as soon as possible when they occur so that they are able to fix them as quickly as possible. Continually deploy -- Through a fully automated process, you can deploy and release any version of the software to any environment. Tools / tool types Continuous delivery takes automation from source control all the way through production. There are various tools that help accomplish all or part of this process. These tools are part of the deployment pipeline which includes continuous delivery. The types of tools that execute various parts of the process include : continuous integration, application release automation, build automation, application lifecycle management. Architecting for continuous delivery To practice continuous delivery effectively, software applications have to meet a set of architecturally significant requirements ( ASRs ) such as deployability, modifiability, and testability. These ASRs require a high priority and can not be traded off lightly anymore. Implementation and usage The CD book written by Jez Humble and David Farley popularized the term, however since its creation the definition has continued to advance and now has a more developed meaning. Companies today are implementing these continuous delivery principles and best practices. Difference in domains, e.g. medical vs. web, are still significant and affect the implementation and usage. Well - known companies that have this approach include Yahoo.com, Amazon.com, Facebook, Google, Paddy Power and Wells Fargo. Benefits and obstacles Several benefits of continuous delivery have been reported. Accelerated Time to Market : CD lets an organization deliver the business value inherent in new software releases to customers more quickly. This capability helps the company stay a step ahead of the competition. Building the Right Product : Frequent releases let the application development teams obtain user feedback more quickly. This lets them work on only the useful features. If they find that a feature is n't useful, they spend no further effort on it. This helps them build the right product. Improved Productivity and Efficiency : Significant time savings for developers, testers, operations engineers, etc. through automation. Reliable Releases : The risks associated with a release have significantly decreased, and the release process has become more reliable. With CD, the deployment process and scripts are tested repeatedly before deployment to production. So, most errors in the deployment process and scripts have already been discovered. With more frequent releases, the number of code changes in each release decreases. This makes finding and fixing any problems that do occur easier, reducing the time in which they have an impact. Improved Product Quality : The number of open bugs and production incidents has decreased significantly. Improved Customer Satisfaction : A higher level of customer satisfaction is achieved. Obstacles have also been investigated. Customer preferences : Some customers do not want continuous updates to their systems. This is especially true at the critical stages in their operations. Domain restrictions : In some domains, such as telecom and medical, regulations require extensive testing before new versions are allowed to enter the operations phase. Lack of test automation : Lack of test automation leads to lack developer confidence and can prevent using continuous delivery. Differences in environments : Different environments used in development, testing and production can result in undetected issues slipping to the production environment. Tests needing a human oracle : Not all quality attributes can be verified with automation. These attributes require humans in the loop, slowing down the delivery pipeline. Strategies to overcome adoption challenges Several strategies to overcome continuous delivery adoption challenges have been reported. Strategies to Overcome CD Adoption Challenges Strategy Description Selling CD as a painkiller Identify each stakeholder 's pain points that CD can solve, and sell CD as a painkiller to that stakeholder. This strategy helps to achieve buy - in from the wide range of stakeholders that a CD implementation requires. Dedicated team with multi-disciplinary members Without a dedicated team, it can be hard to progress because employees are often assigned to work on other value streams. A multi-disciplinary team not only provides the wide range of skills required for CD implementation but also smooths the communication with related teams. Continuous delivery of continuous delivery Organize the implementation of CD in a way that delivers value to the company as early as possible, onboarding more projects gradually, in small increments and eventually rolling out CD across the whole organization. This strategy helps justify the investment required by making concrete benefits visible along the way. Visible benefits, in turn, help to achieve the sustained company support and investment required to survive the long and tough journey to CD. Starting with easy but important applications When selecting the first few applications to migrate to CD, choose the ones that are easy to migrate but that are important to the business. Being easy to migrate helps to demonstrate the benefits of CD quickly, which can prevent the implementation initiative from being killed. Being important to the business helps to secure the required resources, demonstrates clear and unarguable value, and raises the visibility of CD in the organization. Visual CD pipeline skeleton Give a team a visual CD pipeline skeleton that has the full CD pipeline view but with empty stages for those they can not implement yet. This helps to build up a CD mindset and maintain the momentum for CD adoption. The pipeline skeleton is especially useful when the team 's migration to CD requires a large effort and mindset changes over a long period of time. Expert drop Assign a CD expert to join tough projects as a senior member of the development team. Having the expert on the team helps to build the motivation and momentum to move to CD from inside the team. It also helps to maintain momentum when the migration requires a large effort and a long period of time. See also Application lifecycle management Application release automation Build management Change management Continuous configuration automation Continuous integration Continuous testing DevOps Release management Software configuration management Version control WinOps Further reading Humble, Jez ; Farley, David ( 2010 ). Continuous Delivery : Reliable Software Releases Through Build, Test and Deployment Automation. Addison - Wesley. ISBN 978 - 0 - 321 - 60191 - 9. Wolff, Eberhard ( 2017 ). A Practical Guide to Continuous Delivery. Addison - Wesley. ISBN 978 - 0 - 134 - 69147 - 3. References ^ Jump up to : Chen, Lianping ( 2015 ). `` Continuous Delivery : Huge Benefits, but Challenges Too ''. IEEE Software. 32 ( 2 ) : 50 -- 54. doi : 10.1109 / MS. 2015.27. Jump up ^ Hammond, Jeffrey ( 9 September 2011 ). `` The Relationship between DevOps and Continuous Delivery ''. Forrester Research. Forester. ^ Jump up to : Humble, Jez ; Farley, David ( 2011 ). Continuous Delivery : reliable software releases through build, test, and deployment automation. Pearson Education Inc. ISBN 978 - 0 - 321 - 60191 - 9. Jump up ^ Swartout, Paul ( 2012 ). Continuous Delivery and DevOps : A Quickstart guide. Packt Publishing. ISBN 978 - 1849693684. Jump up ^ `` bliki : ContinuousDelivery ''. martinfowler.com. Retrieved 2015 - 10 - 29. Jump up ^ Jez Humble ; Chris Read ; Dan North ( 2006 ). `` The Deployment Production Line ''. IEEE Computer Society. Proceedings of Agile 2006. Jump up ^ Fitzgerald, Brian ( 2014 - 06 - 03 ). Continuous Software Engineering and Beyond : Trends and Challenges ( PDF ). 1st International Workshop on Rapid Continuous Software Engineering. New York, NY : Association for Computing Machinery. pp. 1 -- 9. ISBN 978 - 1 - 4503 - 2856 - 2. doi : 10.1145 / 2593812.2593813. Retrieved 2014 - 10 - 24. Jump up ^ Kluge, Lars ( 12 September 2013 ). `` Continuous Deployment with MongoDB at Kitchensurfing ''. slideshare.net. Retrieved 3 January 2014. Jump up ^ Duvall, Paul ( 2012 ). `` Continuous Delivery : Patterns and Anti-Patterns in Software Lifecycle '' ( PDF ). Refcardz. Retrieved October 9, 2015. Jump up ^ Phillips, Andrew ( 29 July 2014 ). `` The Continuous Delivery Pipeline -- What it is and Why it 's so important in Developing Software ''. DevOps.com. Retrieved October 9, 2015. Jump up ^ Binstock, Andrew ( 16 September 2014 ). `` Continuous Delivery : The Agile SUccessor ''. Dr. Dobb 's The world of software Development. San Francisco : UBM. Jump up ^ Chen, Lianping ( 2015 ). Towards Architecting for Continuous Delivery. The 12th Working IEEE / IFIP Conference on Software Architecture ( WICSA 2015 ). Montréal, Canada : IEEE. ^ Jump up to : Leppänen, M. ; Mäkinen, S. ; Pagels, M. ; Eloranta, V.P. ; Itkonen, J. ; Mäntylä, M.V. ; Männistö, T. ( 2015 - 03 - 01 ). `` The Highways and Country Roads to Continuous Deployment ''. IEEE Software. 32 ( 2 ) : 64 -- 72. ISSN 0740 - 7459. doi : 10.1109 / MS. 2015.50. Jump up ^ `` Implementing Continuous Delivery at Yahoo ! ''. confreaks.tv. 23 October 2013. Jump up ^ Humble, Jez ( 13 February 2014 ). `` The Case for Continuous Delivery ''. thoughtworks.com. Retrieved 16 July 2014. Jump up ^ jFrog ( December 2014 ). `` 2014 - year - continuous - integration - revolution ''. Jump up ^ Chen, Lianping ( 2017 ). `` Continuous Delivery : Overcoming adoption challenges ''. Journal of Systems and Software. 128 : 72 -- 86. doi : 10.1016 / j. jss. 2017.02. 013. Retrieved from `` https://en.wikipedia.org/w/index.php?title=Continuous_delivery&oldid=800238249 '' Categories : Software release Software design Software development process Hidden categories : Wikipedia articles needing clarification from September 2017 All articles with unsourced statements Articles with unsourced statements from April 2015 Talk Contents About Wikipedia Deutsch Español فارسی 한국어 Nederlands Svenska Tiếng Việt 中文 Edit links This page was last edited on 12 September 2017, at 08 : 05. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: what do the three continuous cycles on the continuous delivery pipeline enable
Answer: software can be reliably released at any time