In parallel, software development has seen a steady evolution. Driven by the scale of software content in everyday applications, continuous integration (CI) has become absolute necessary for software development teams to meet products’ performance requirements. CI refers to the practice of software developers merging their code changes into a shared mainline code base, or a main repository, often multiple times a day to test their performance.
Traditionally, DevOps teams had to merge the code changes from all the programmers at designated checkpoints. By that time, individual portions of the code often deviated drastically, which in turn resulted in a challenging integration step to debug and fix any problems. In contrast, CI allows teams to view and fix incompatibility issues early on, therefore resolving them more easily and cost-efficiently.
A robust, highly automated build and test cycle is needed for CI to work properly. This system quickly ensures that the changes being submitted are tested in the context of the latest software stack and that they don’t break existing functionality. It can also provide quick feedback to software developers on key areas such as code coverage, quality, and effectiveness.
CI is also often coupled with continuous deployment (CD), a process in which any code build that has successfully passed through all automated tests is deployed into production. CD takes the practice of CI one step further to automate the code release process so that once new codes are merged into the main repository and have passed all automated testing, they can be pushed into production in a streamlined process.