Continuous Integration and Delivery in an Agile Environment

What are continuous integration and continuous delivery?

CI/CD are software development and DevOps best practices.

“CI” stands for continuous integration, while “CD” can mean either continuous delivery or continuous deployment.?

Continuous integration is not merely a technology or a methodology; it’s a whole culture that has a set of rules, principles, and practices for fast and reliable software development. The implementation of this culture into a development process is called the CI/CD pipeline.

It’s not easy to implement CI/CD into the project, because it requires lots of resources on writing the automated tests. However, in the long run it accelerates the development process and helps our clients to get a more high-quality code that’s easy to test and maintain

Yulia Kutsokon, project manager at Mobindustry

CI/CD is perfect for Agile development, as it focuses on flexibility, code quality, and constant testing. The purpose of continuous integration is to save time on future maintenance and testing, as the code is tested each time it’s merged, which often happens every day or even several times a day. It integrates perfectly with the?lean startup principles, as well as best practices of any Agile software development.

What is continuous integration model and what is continuous delivery? These two methodologies often go hand in hand, but let’s define these terms separately first for better understanding. Then, we’ll discuss how to implement continuous delivery into your project.

How to do CI/CD right in your development process

Continuous integration and continuous delivery is a set of rules and principles that you need to integrate into your everyday development pipeline. Here are the things you need to do in order for CI/CD to work to your benefit.?

Write automated tests

Automated testing is one of the most important principles of CI/CD. Your developers should write automated tests for each new feature, bug fix, or improvement with the help of automated testing frameworks. These automated tests will determine whether a certain build passes and can be merged into the main branch without any issues.

All tests for functionality should be aggregated into a regression test for the entire app after every sprint, in each developer’s local environment. Thus, a developer will be able to commit code to version control only after it passes regression testing.?

Note that you can also automate other kinds of testing like security testing, API testing, performance testing, and static code analysis. After tests are automated, they can be integrated into your continuous integration pipeline.

Set up a CI server

A continuous integration server monitors the main repository and can run thousands of tests automatically when each committed piece of code is pushed.?

A CI server is also called a build server, and it initiates a build each time new code comes in and documents whether it’s successful.

Merge often

For CI/CD to be successful, developers need to merge code as often as possible to find issues early and accelerate the development process. According to CI best practices, merging should happen at least once a day.

Develop a build schedule

The frequency of initiating builds depends on the team size, expected daily commits, and business demands. You need to discuss the build schedule with your team beforehand and take all factors into account.?

CI/CD suggests fast commits and builds, so the team is motivated to code and commit frequently and do as many iterations as possible.

Automate deployments

Deployments should also be automated. Though they can still be triggered manually according to continuous delivery, the human intervention stops there, and the deployment process happens automatically.

Use feature flags

A feature flag is a CI configuration mechanism that allows developers to switch both code and separate features on or off during runtime. Feature flags wrap features that are still being developed. Developers can deploy those features to production and turn them off until they’re ready for use. Thus, you can deploy new features to the production environment and give access to certain users while hiding them from other users.

For example, you can give internal users access to new features so they can test them or give feedback, but these features won’t be available for your external users. Essentially, feature flags are used to make changes to the main branch without having to maintain multiple branches within your source code.

Optimizely Rollouts, LaunchDarkly, and CloudBees Rollout are some of the most popular feature flagging tools on the market.

Use version control branching

Version control branching is another popular strategy that defines how new code is merged into branches for testing, development, and production. Developers also often add additional branches for features that will take longer to develop, test, and deploy.?

If you want to learn more about CI/CD in software development, check the full article here.