Key Differences between Continuous Integration, Continuous Delivery & Continuous Deployment

November 02, 2017 | Sachin Parikh

Over the past few years, Continuous Delivery, Continuous Integration, and Continuous Delivery have become a part of our daily technology vocabulary. As we continue to implement these practices into our Application Lifecycle Management (ALM) workflows, these three terminologies can be confusing.

In this post, we will define each of these processes and how they work together so that stakeholders, developers and project managers can work in alignment in one integrated environment.

Continuous Integration

Continuous Integration (CI) is the process of automating the build and testing of code every time a team member commits changes to version control. CI encourages developers to share their code and unit tests by merging their changes into a shared version control repository after every small task completion. Committing code triggers an automated build system to grab the latest code from the shared repository and to build, test, and validate the full master branch. In the continuous integration process, most of the work is done by an automated test technique, which requires a unit test framework. It is a best practice to have a build server designed specifically for performing these tests, so your development team can continue merging requests even while tests are being performed.

Continuous Delivery

Continuous delivery is a series of practices designed to ensure that code can be rapidly and safely deployed to production by delivering every change to a production-like environment and ensuring business applications and services function as expected through rigorous automated testing. Since every change is delivered to a staging environment using complete automation, issues and bugs can be identified and fixed beforehand, and users can have the confidence that the application can be deployed to production with one click when the business is ready.

Continuous Deployment

Every change that passes the automated tests is deployed to production automatically. Continuous deployment relies on small changes, which are constantly tested, deployed, and released to production immediately upon verification. The ownership of the code from development to release must be controlled by the developer and must be free-flowing. The automation of steps allows this process to be implemented and executed without cumbersome workflows. Post-deployment, logs must be inspected to validate whether any key metrics are affected—positively or negatively. Continuous deployment should be the goal of most companies that are not constrained by regulatory or other requirements.

How they work together

When you’re ready for deployment, you need to have your automation in place. Automate your continuous integration build server and continuous delivery to staging, which gives you the ability to automatically deploy to production. This means you will automate the entire process from start to finish.