Why Is Continuous Integration So Critical in Software Development?
As software projects grow in size and complexity, the need for better tools and processes to manage that complexity becomes more important. Continuous integration (CI) is one of those tools, and it’s importance cannot be overstated.
Continuous integration (CI) is a process that helps manage complexity by integrating changes to a codebase as often as possible. This integration is done in a controlled environment, typically a CI server, which runs automated tests against the changed code. If the tests pass, the code is integrated into the main codebase. If they fail, the code is rejected and the developer is notified of the failure.
The need for Continuous Integration in Agile team is more because as the product owner changes the priority of the user stories, the developers need to be able to quickly adapt and get the changed code working. Product owners change priority to accommodate customer needs, customer feedback, and business goals.
Traditional software development is built up of “sprints”: You develop your code for two weeks and introduce the changes during a sprint. These changes are then tested, sometimes by the developer implementing these changes, to see if there are any problems. If problems occur, fixes are worked out until everyone is happy with the system. Then the project is integrated, i.e., changes made by one developer must be merged into the repository. Only after this is the complete system tested again. Finally, the system goes into production under full testing and final verification to get the end customer’s approval. Of course, the software will always contain bugs, even if the software is tested and bug-free. When these bugs are identified, they usually need to be fixed by one of the developers, who will then spend additional time to do so.
There are a couple of problems with this approach. The first is that it’s easy for integration problems to remain hidden when the integration process takes place only once a week. Only then does the developer have time to work out all of the issues. That’s a second problem. And the third problem is that the testing takes place on a branch of the repository, making it harder to catch bugs before integration.
The benefits of CI are many.
First, it helps ensure the quality of the codebase by catching errors and regressions early because if you’re able to run the latest code against the latest code, and your code isn’t broken, it should pass the tests.
Second, it helps developers catch integration problems early, before they become too difficult to fix.
Third, it helps developers to become more agile, by allowing them to quickly and easily integrate changes into the codebase.
Finally, it helps to ensure that the codebase is always in a usable state.
In short, CI is a vital tool for managing the complexity of large software projects. It helps to ensure the quality of the codebase, while also helping developers to be more agile and productive.