Continuous improvement is the mantra of DevOps. And, as with many mantras, continuous improvement is easy to talk about but harder to put into practice. It takes work to translate the concept into changes on the ground. But it's certainly not impossible. To illustrate what continuous improvement looks like in practice, let's examine strategies to improve CI/CD processes by expanding on and optimizing the CI/CD model that is already in place.
What Is CI/CD?
CI/CD refers to the set of processes by which software is continuously written and deployed. It stands for continuous integration/continuous delivery (or continuous integration/continuous deployment, depending on whom you ask).
Although DevOps is about more than just CI/CD, the CI/CD concept is what helps differentiate DevOps from earlier approaches to software delivery. When the processes required to write and deploy software are continuous--meaning that application changes are produced and applied to production environments constantly--it becomes much easier to achieve core DevOps goals, such as collaboration between developers and IT operations teams.
How to Improve CI/CD Processes
If your organization practices DevOps, it's likely that you already have at least a basic set of CI/CD processes and tools in place. However, there's almost certainly room for improvement. Here are recommendations for five strategies organizations can put into place to optimize their CI/CD processes and pipeline.
1. Automated testing
You probably already run some tests as part of your CI/CD pipeline. Indeed, it's hard to imagine a reliable CI/CD pipeline that doesn't include testing to catch software errors before they reach production.
But if you're not automating those tests as much as possible, you're missing out on a key opportunity to improve CI/CD processes. Test automation makes tests faster, repeatable and easier to update. It also helps you run tests in parallel, which in turn allows you to run more tests without slowing down the CI/CD cycle.
2. Canary releases
Part of the purpose of CI/CD pipelines is to enable teams to push out application changes rapidly. Rapid deployments means that your end users get improvements faster. But speed also increases the risk that you'll accidentally introduce a problem into your production environment, which in turn harms your end users.
One way to mitigate this risk--albeit not avoid it entirely--is the canary release technique. A canary release strategy entails releasing software changes to a subset of your end users, then monitoring them closely for signs of trouble. That way, if something goes wrong, only some of your users are impacted.
Executing canary releases requires fine-grained control over your release process (to ensure that you can deploy to some users but not others), and it adds complexity to the CI/CD pipeline. It also requires thorough monitoring of your production environment to catch issues that may arise within your group of canary users. But it's worth it if it means a more reliable deployment process.
3. Blue/green deployment
Another technique for deploying rapidly while mitigating the risk of problems in production is blue/green deployment. Under this approach, you maintain two production-like environments: a "blue" environment and a "green" environment. At any given time, only one of these environments hosts software that faces end users.
When you have a new release to deploy, you deploy it into the environment that is not currently supporting end users. You then test it out in that environment. Once you confirm that it performs as expected, you redirect traffic so that the new environment faces your end users.
The chief benefit of blue/green deployment is that it eliminates the risk that a failed deployment will impact end users. The major downside is that it requires two production-like environments, which essentially doubles the size of the infrastructure you need to maintain (and pay for). But it may be worth the cost as a way to improve CI/CD processes and reliability.
4. Software composition analysis
Software composition analysis, or SCA, refers to processes that help you determine where source code within your application codebase originated, and then identify risks or problems in the code. SCA is especially useful if you incorporate third-party code (such as code from an open source project) into your own codebase.
SCA doesn't tend to be a core part of CI/CD pipelines, but it's an obvious way to improve your pipeline if you rely in part on third-party code and want to minimize the potential security or reliability risks in it.
5. CI/CD branching
When you have a large-scale CI/CD process that involves many developers, all of them working on different features at the same time, CI/CD branching can make the overall CI/CD pipeline faster and more efficient.
Branching allows you to divide different versions of your application into so-called branches. One of them is typically a "main" branch, which contains stable code. Other branches include code for additional features that have not yet been fully tested. Once features have been tested, they can be merged into the main branch. By breaking your codebase into branches, it becomes easier to add and vet new features without risking the stability of the main codebase.
Branching may be overkill for simple CI/CD pipelines, but it's a great way to organize your CI/CD processes as they grow and become more complex.
Although continuous improvement may sound like a fluffy idea, there are practical ways to improve the CI/CD processes that are the core of any DevOps operation. From automated testing to smarter deployment processes to SCA and beyond, you can almost certainly make your CI/CD pipeline faster, more efficient and more reliable.