What Is CI/CD? (Continuous Integration/Continuous Deployment)

Continuous Integration (CI) is a software development practice where developers regularly merge their code changes into a central repository, multiple times a day or even after every commit. After each integration, automated builds and tests are run to catch bugs as early as possible.

Continuous Deployment (CD) is a software release process that uses automated testing to validate if changes to a codebase are correct and stable for immediate autonomous deployment to a production environment. It’s a step further than Continuous Delivery, a similar concept, but requires manual approval to deploy to production.

Related content: Read our guide to continuous integration vs continuous delivery and our guide to continuous integration vs continuous deployment.

Together, they form CI/CD, a method that allows software development and IT teams to deliver code changes more frequently and reliably. It’s an approach that focuses on making the process of integrating and deploying code as seamless as possible.

This is part of an extensive series of guides about Kubernetes.

In this article:

Why Is CI/CD Important in Modern Software Development?

CI/CD has become an integral part of modern software development for several reasons. It’s not just about delivering software faster—it’s about improving quality, productivity, and risk management in the software development process.

Faster Release Cycles

CI/CD plays a crucial role in enabling faster release cycles. By automating the integration and deployment processes, teams can push out updates more regularly, often multiple times a day. This not only allows businesses to adapt to changes swiftly but also gives them a competitive edge.

Improved Code Quality

CI/CD also significantly improves code quality. With the ability to catch bugs early and fix them quickly, teams can reduce the number of errors in the final product. This leads to enhanced user experience and increased customer satisfaction.

Enhanced Developer Productivity

One of the most significant benefits of CI/CD is enhanced developer productivity. Developers can focus on writing code rather than spending time on manual tasks like integrating changes and deploying code. This leads to higher efficiency and allows teams to deliver more value to the business.

Reduced Deployment Risks

Lastly, CI/CD helps reduce deployment risks. By automating the process and deploying smaller changes more frequently, teams can reduce the chances of a failed deployment. This not only saves time but also ensures a stable and reliable product.

3 Core Concepts of CI/CD

The concepts of Continuous Integration, Continuous Delivery, and Continuous Deployment form the backbone of the CI/CD approach. Understanding these concepts is crucial to leverage the power of CI/CD effectively.

Continuous Integration

Continuous Integration is all about integrating changes frequently. It focuses on ensuring that the codebase is always in a deployable state. This is achieved by running automated tests every time a change is made. This way, any issues are identified and resolved quickly, leading to a more stable codebase.

Continuous Delivery

Continuous Delivery takes Continuous Integration a step further. It not only ensures that the codebase is always in a deployable state but also makes sure that the code can be deployed to production at any time. This is achieved by keeping the production-ready build artifact always available.

Continuous Deployment

Continuous Deployment, the most mature stage of the CI/CD approach, automates the entire process from code commit to production deployment. Every change that passes the automated tests is automatically deployed to production. This approach ensures that the software is always in a state that can be released, allowing for much faster delivery times.

CI/CD Pipeline Stages

A CI/CD pipeline is a framework for automating the processes involved in software development. It includes a series of stages that the code needs to pass through before it is ready for deployment.

Development

The process begins at the development stage. In this phase, developers write and commit changes to the code. The updated code is then pushed to a shared repository. This allows for collaboration among team members and ensures that everyone is working on the most recent version of the code. Version control systems like Git are commonly used for this purpose.

Build

The next stage in the CI/CD pipeline is the build stage. This involves compiling the code into an executable form. In this phase, the code is taken from the shared repository and various actions such as compiling, linking, and packaging are performed to create a build. Build tools like Maven, Gradle, or Ant can be used for this purpose.

Learn more in our detailed guide to ci/cd tools.

Testing

The testing stage is crucial for ensuring the quality of the code. Automated tests are run to check the functionality, performance, and security of the code. Any bugs or issues detected are flagged for correction. Testing tools like Junit, Selenium, or TestNG can be used for this purpose.

Deployment

In the deployment stage, an artifact or a deployable piece of software is created. This artifact is stored in an artifact repository from where it can be retrieved for deployment. Finally, the artifact is automatically deployed to production. In Continuous Delivery, this occurs upon manual approval of the artifact, and in Continuous Deployment it happens without human intervention.

Learn more in our detailed guide to CI/CD process (coming soon)

CI/CD Challenges

Despite the numerous benefits of CI/CD, implementing it comes with its own set of challenges. These hurdles can range from resistance within the organization to technical difficulties in setup and maintenance.

Cultural Resistance

One of the biggest challenges in implementing CI/CD is cultural resistance within the organization. The shift to CI/CD requires a significant change in the way teams work and requires them to embrace a culture of collaboration and transparency. This may be met with resistance, especially in organizations with a traditional hierarchical structure.

Complexity in Setup and Maintenance

Setting up a CI/CD pipeline can be a complex task that requires a considerable investment of time and resources. Maintaining the pipeline, especially in the face of frequent changes and updates, can also pose a challenge.

Deployment Challenges

Deployment poses another set of challenges. This includes ensuring that the deployment process is smooth and error-free, and managing the different environments in which the software will be deployed. Managing dependencies and coordinating releases can also be complex tasks.

Ensuring Security

Ensuring security in a CI/CD pipeline is critical. This includes protecting the code, the pipeline, and the environments in which the software is deployed. Security measures need to be integrated into every stage of the pipeline, from source to deployment.

Best Practices for Successful CI/CD

Maintain a Version Control System

The first step in implementing a successful CI/CD pipeline is having a reliable Version Control System (VCS). Version control is the practice of tracking and managing changes to your code. It allows you to keep a history of your project, so you can go back to any previous version if needed.

A VCS is crucial for CI/CD because it allows you to integrate changes continuously. When developers commit their changes to the VCS, it triggers the CI/CD pipeline, which will then build, test, and deploy the new version of the software. By maintaining a VCS, you can ensure that every change is integrated and validated, reducing the risk of introducing bugs into the production environment.

Keep the Build Fast

Another important principle in CI/CD is to keep the build fast. A slow build process can become a bottleneck in your CI/CD pipeline, causing delays in the deployment of new features and bug fixes. This can lead to frustration among your team and can diminish the benefits of CI/CD.

Keeping the build fast requires careful management of your build process. This can involve optimizing your build scripts, using build caches, and parallelizing your build tasks. You should also monitor your build times and take action when they start to increase. A fast build process not only speeds up your CI/CD pipeline but also provides faster feedback to your developers, helping them to catch and fix issues more quickly.

Ensure a Single Source of Truth

In the realm of CI/CD, it is crucial to have a single source of truth. This means that there should be one, and only one, place where your code, configuration, and other resources live. Having a single source of truth ensures that everyone on your team is working with the same information, reducing the potential for conflicts and misunderstandings.

A single source of truth also helps to make your CI/CD pipeline more reliable. When your CI/CD tools always pull code and resources from the same place, you can be sure that your build and deployment processes are consistent and repeatable. This will help to eliminate surprises and make your releases more predictable.

Use Feature Toggles

Feature toggles, also known as feature flags or switches, are a powerful tool in the CI/CD arsenal. They allow you to enable or disable features in your application without changing the code. This can be especially useful in a CI/CD context, where you want to be able to deploy new features quickly but still have the option to turn them off if they cause problems.

Feature toggles can also support a practice known as trunk-based development, where all developers work on a single branch (the “trunk”) and integrate their changes frequently. With feature toggles, you can merge new features into the trunk even if they are not ready for release. The feature can be hidden behind a toggle until it is ready, allowing you to continue integrating and testing it in the meantime.

Foster Collaboration and Communication

CI/CD is not just about tools and technology; it’s also about people and culture. To fully unlock the power of CI/CD, you need to foster collaboration and communication within your team.

CI/CD encourages a culture of shared responsibility, where everyone is involved in delivering the software. Developers need to work closely with testers, operations, and other stakeholders to ensure that the software is built, tested, and deployed smoothly. This requires clear communication and a willingness to work together towards a common goal.

Secure the CI/CD Pipeline

Last but not least, it is vital to secure your CI/CD pipeline. As your pipeline becomes more integrated with your development process, it also becomes a more attractive target for attackers. A breach in your CI/CD pipeline can lead to serious consequences, including unauthorized access to your code, manipulation of your build process, or even deployment of malicious software.

Securing your CI/CD pipeline involves multiple aspects, including securing your source code, protecting your build environment, and monitoring your pipeline for suspicious activity. It also involves educating your team about security best practices and fostering a culture of security awareness.

In conclusion, CI/CD is a powerful practice that can dramatically improve your software development process. By following these best practices, you can unlock the full potential of CI/CD and deliver higher quality software at a faster pace.

Related content: Read our guide to CI/CD as a service

CI/CD for Kubernetes with Spot by NetApp

Continuous Delivery has entered a new phase as more and more applications are migrating to microservices, with Kubernetes as the container orchestrator of choice for many. Kubernetes enables agility and faster software development cycles, but as release frequency increases, supporting delivery at large-scale becomes complex and inefficient.

Learn more in our detailed guide to kubernetes ci cd and kubernetes ci cd tools.

Spot by NetApp introduced Ocean CD as part of the Ocean suite for Kubernetes to address the specific challenges of modern delivery release cycles. Ocean CD provides complete deployment and verification automation in one fully managed solution, making it easy for users to execute deployments with high confidence. Key features of Ocean CD include:

Out-of-the-box progressive delivery strategies

Canary and blue/green strategies are easy to define, automate and customize. Developers commit code, use any CI tool and Ocean CD detects the deployments, automatically initiating the assigned rollout strategy.

Continuous verification automation

Ensure stability and quality of deployments even as release frequency increases. Routine verifications of deployments are conducted automatically and based on metrics from monitoring tools like DataDog and New Relic.

Learn more in our detailed guide to devops automation.

Automatic rollback

When issues are detected, Ocean CD initiates safe rollbacks and automatically tunes infrastructure to meet changing requirements of workloads. Continuous improvements are made to application deployments based on metrics collected during verification processes.
To learn more about Ocean for Continuous Delivery read our blog post or visit the product page.

See Additional Guides on Key CI/CD Topics

Together with our content partners, we have authored in-depth guides on several other topics that can also be useful as you explore the world of Kubernetes.