Curious about continuous integration? Here’s what you need to know

In the days before continuous integration (CI), developers worked on code separately before bringing it all together in the final build. With this approach, the chance of error is high. Waiting long periods to integrate large amounts of code means that if something is amiss, it’s a real headache to weed the problem out.

There’s also a considerable communication burden on everyone as the project grows. Bigger jobs require more engineers, developers, and project owners to be sensitive to each other’s schedules. It also demands a great deal of synchronization, which, let’s face it, is an organizational nightmare.

Automating as much of the build-release cycle as possible can go a long way towards alleviating these developer pains. This is where continuous integration (CI) comes in. Read on to discover what continuous integration is, how it works, and the tools you need to get started.

What is continuous integration?

Continuous integration is the first stage in the automated software release pipeline. It’s followed by continuous delivery and then, finally, continuous deployment. It takes its lead from other agile software development best practices, including build automation, version control, and automated deployments.

With continuous integration, code merges in a central repository. Once it’s all in there, the team can run automated builds and tests at the click of a button.

Having this level of automation means the developers have more time to work on other things. Meanwhile, the fact that a machine creates the code lowers the chance of human error. In a nutshell, it helps developers work faster, improves code quality, and shortens the time between new releases.

What is continuous integration in Agile?

Agile refers to all and any kind of software development approach that involves iterative development. In other words, solutions are reached gradually through teams that work together and self-organize.

As you’ve probably worked out, continuous integration fits this description. The project manager will create a list of tasks that are shared with the developers responsible for completing them.

Continuous integration allows developers to work on groups of tasks both independently and in parallel. Once the developer completes a task, they are responsible for feeding it into the CI system, where it will integrate with the rest of the build project.

Key features of continuous integration:

• Automated testing: With CI, a test suite acts according to a set of assertions that assures the primary code base is working correctly. Developers run these tests on new code to make sure it hasn’t caused any regression.

• Source version control: Version Control Systems (VCS) are a cornerstone of continuous improvement. Developers use it to resolve conflicts between multiple inputs in the same codebase. It also means developers can recover an exact snapshot of the state of the entire system at any point in the project’s history.

• Build automation: ‘Builds’ are snapshots of the progress at any given time. With CI, these snapshots are delivered to the customer via a series of automatic triggers. This makes the whole process faster and less bureaucratic.

• Automated deployments: The build is automatically deployed to a publicly accessible server, where it can be downloaded or accessed by the client.

What are the advantages of continuous integration?

CI benefits the whole organization, as well as the customer. Teams work more collaboratively and transparently, which means projects can move faster and with a higher degree of certainty.

• Enhanced communication: Because developers are working in parallel, they can view and comment on other’s code as well as collaborate on build branches. CI also promotes a greater feeling of progress and trust. Before code is merged, it needs to pass a CI test that ensures new features match the specifications. This prevents errors and regressions.

• Better scaling: With a no-CI system, the bigger a project gets, the more code there is, the more people there are involved, and – you guessed it – the more complicated it becomes. With CI, each team member has responsibility for their own code from initial creation through to release. And they feel safe in the knowledge that it will integrate perfectly with the rest of the build. Allowing the team to self-organize in this way removes the need for time-consuming micromanagement.

• A more agile way of working: The iterative nature of CI means feedback comes in thick and fast. This means changes can be made and measured quickly, while bugs can be fixed quickly and cheaply because the amount of code to go through is that much smaller.

How to pick continuous integration tools for your team

Some of the most popular continuous integration include GitLab, SVN, and Jenkins. Whichever your team chooses, you’ll benefit from being able to track and review your code for better releases – so be sure to choose an issue tracking software that supports your choice.

Next, consider whether you want a CI tool that is on-site or cloud-based. If you choose the former, your security and privacy will be better, but you’ll be responsible for managing the infrastructure yourself. If you select something cloud-based, the hosting company will take care of support and scaling, meaning you and your team can focus on other business needs. This is especially useful for smaller organizations working with a more modest budget.

Finally, consider container support. As containers become ever-more popular, dev teams need more efficient ways to manage their systems. Kubernetes, or K8s for short, is the most popular open-source container orchestration tool. It’s used for bundling and managing clusters of containerized applications – a process known as ‘orchestration’ in the computing world. Proper CI tools offer support for integrating various containers, including Kubernetes.

Final thoughts

If you work with a multi-developer team, then CI is a must. It’ll speed up deployments, reduce the risk of code errors, and foster greater levels of communication between your team and the rest of the organization.

To really get aligned, consider integrating your CI tools with project management software. Developers can log in and track their work, pull tasks through, and receive automatic notifications from their colleagues.

If you’re on the lookout for software that does all that and more, Backlog integrates fully with Git and SVN, giving your team the ability to set up private repositories, propose and compare code changes, and leave in-line comments. All the while, managers can access progress reports that give that all-important view into your team (and organization’s) performance.

Want to learn more about the full software development lifecycle? Make sure to check out our DevOps Guide.