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 and, following a pipeline through a "production-like environment", without doing so manually. It aims at building, testing, and releasing software with greater speed and frequency. 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. Continuous delivery contrasts with continuous deployment (also abbreviated CD), a similar approach in which software is also produced in short cycles but through automated deployments even to production rather than requiring a "click of a button" for that last step. As such, continuous deployment can be viewed as a more complete form of automation than continuous delivery. Continuous delivery and DevOps are similar in their meanings and often conflated, but they are two different concepts. DevOps has a broader scope, and centers around 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 frequently. Thus, DevOps can be a product of continuous delivery, and CD flows directly into DevOps. Continuous deployment Continuous delivery is the ability to deliver software that can be deployed at any time through manual releases; this is in contrast to continuous deployment which uses automated deployments. According to Martin Fowler, continuous deployment requires continuous delivery. Academic literature differentiates between the two approaches according to deployment method; manual vs. automated.