There are two main phases of the automated software release pipeline. First is continuous integration, where developers build, test, and combine code changes into the main software branch, and second is continuous delivery, where developers enable code to be released for production in short cycles.
The biggest advantage of continuous delivery is that it gives development teams the capability to build, test, and deploy software quickly through automation, APIs, and incremental updates, a major improvement from the time-consuming overhauling of large product code portions.
CD makes feedback loops incredibly efficient as well, allowing developers to continuously improve software quality. Code delivery to staging environments occurs on a regular basis, allowing automated testing for functionality and performance in production.
Continuous delivery in DevOps
Continuous delivery integrates automation into a software delivery process and is an important part of DevOps strategies. Continuous delivery allows developers to write and commit pieces of distributable code to testing environments, enabling efficient, automated testing.
With this automated testing, development teams can rapidly determine whether the new pieces of distributable code meet quality standards. This accelerates the release of software improvements while still maintaining the security and integrity of an organization’s data.
Continuous delivery also provides what is known as “shift left” which refers to how testing occurs early on in the release cycle. This allows developers to resolve issues before addressing other facets of development.
Continuous delivery vs Continuous deployment
Although continuous delivery and continuous deployment are both related to continuous integration, the way they facilitate update approval and send updates into production distinguishes them. For instance, in continuous deployment, updates occur automatically without a need for manual approval. By contrast, continuous delivery requires manual approval to send an update live. Ultimately, continuous deployment is just a step further in the automation processes of the CI/CD pipeline.
How do you implement continuous delivery?
Implementing CI/CD practices requires software teams to shift away from outdated development methodologies to DevOps. This necessitates certain resources, like training and seminars, that organizations must prepare in advance.
Additionally, shifting to DevOps for continuous delivery requires both collaboration between developers and operations team and support throughout an entire organization. The latter is a major component to any successfully technological or process shift, especially for CI/CD considering how time-consuming an investment it is. With all parts of an organization aligned on the CI/CD pipeline, DevOps teams can take advantage of a faster feedback loop.
The CI/CD pipeline must also remain compliant with security regulations. Fortunately, the automation capabilities of continuous delivery can be stretched to include security and compliance practices. In fact, certain CI/CD automation tools can even help companies forgo the need for involvement from IT teams.
Additionally, a shift to CI/CD practices can also be compatible with a shift to microservices. As opposed to a monolithic architecture where functional elements are fully connected, microservices separate functional elements so they can even be shipped individually. By using microservices, organizations no longer need to be concerned about altering an entire codebase with every small change. Additionally, monolithic code is not compatible with continuous delivery for multiple reasons, so implementing microservices can help developers circumvent potential issues.
Importance of continuous delivery
Continuous delivery enables development teams to ship out software improvements rapidly. This is in part because by making testing occur earlier in the process and using smaller pieces of code, CD allows developers to replace parts of larger applications without concern for bugs or version control issues.
CD also continuously sustains code in a deployable state. This eliminates the integration, testing, and hardening phases of large releases and uses continual updates to keep releasing code on a smaller scale.
Releasing code on a smaller, incremental scale also quickly exposes bugs in new code, enabling development teams to quickly isolate and address those bugs since they are only apparent in the most recent update.
Development teams can also avoid disabling entire releases by using feature flags to find and disable individual functionalities that are not ready for release or that may cause issues.
Continuous delivery also gives developers access to consistent feedback from users. Customer feedback throughout the delivery lifecycle helps developers quickly test different ideas with users and even build new features that are actually useful to users.