What is CI/CD?
CI/CD is the combined practices of continuous integration (CI) with continuous delivery or continuous deployment (CD). The purpose of CI/CD is to allow development teams to deliver code changes more frequently and reliably.
What’s the difference between continuous integration, continuous delivery, and continuous deployment?
Continuous integration (CI)
The CI in CI/CD stands for continuous integration. Continuous integration means that developers frequently merge their code changes to a shared repository. It’s an automated process that allows multiple developers to contribute software components to the same project without integration conflicts. CI involves automated testing whenever a software change is integrated into the repository.
Continuous delivery or continuous deployment (CD)
CD can stand for either continuous delivery or continuous deployment. Both involve taking the code continuously integrated and getting it able to deploy to an environment either QA or production. Continuous deployment takes the process one step further and performs the actual deployment to an environment.
Why is CI/CD important?
When large pieces of a code base change at a time it puts an application's quality at higher risk. This is because there is more likely a chance that something will break the larger the change - and troubleshooting is harder the larger the change. Agile organizations frequently integrate their code and perform automated tests to reduce the cost of introduction, identifying root causes, and fixing bugs.
Automation is key to CI. There is no way someone could keep up manually at the speed needed for continuous integration to be successful. Developers need to integrate frequently and need feedback as soon as possible.
Continuous delivery and continuous deployment have similar goals, as they use automation to reduce the time, effort, and risk involved in shipping a release. Continuous delivery is quick and efficient. Every build is automatically tested in each environment, and if it passes, the code can be manually deployed with a single click. The preparation is automated, but the push to production is often initiated by the operations team.
With continuous deployment, in which the release to production is fully automated, you relinquish some control. At the same time, you gain additional advantages. You can develop at an even higher velocity than the already-fast continuous delivery, since you don’t need to pause development for releases, and your customers will appreciate the steady stream of improvements.
What are some major challenges with CI/CD?
The benefits of CI/CD are numerous, but implementing the process can present challenges. First, while continuous integration and continuous delivery/deployment are related, they are distinct parts of the CI/CD pipeline. When organizations don’t understand the difference, they can end up implementing CI alone and calling it CI/CD. For a complete CI/CD setup, continuous integration—likely performed with a CI-specific tool—should feed into automated processes for testing, delivery, and deployment.
Organizational misalignment
CI/CD involves many players. As with most DevOps practices, it requires strong collaboration between development, QA, and operations teams—something many organizations struggle with. These teams often have competing priorities: developers want to release quickly and iterate; QA wants to minimize bugs; operations wants safe, stable rollouts. Without clear ownership or communication, these competing goals can slow down or derail CI/CD adoption.
Security gaps in the pipeline
Security is a challenge for every organization, yet it's often treated as an afterthought in the DevSecOps process—when it should be integrated early as possible in the pipeline. In many cases, security controls aren't introduced until late in the pipeline—when issues are more costly and complex to fix. To be truly effective, security must be integrated early in the software development life cycle (SDLC) using a shift left security approach. This allows teams to detect and resolve security risks during earlier, lower-cost stages of development.
Implementation and automation barrieres
Knowing where and how to begin with CI/CD is another major challenge. Frequent, repetitive tasks—like testing, code review, and deployment—are prime candidates for automation. But without clear guidance or executive buy-in, teams often delay automation or implement it inconsistently. A good strategy is to start with a small, focused team and implement basic automation to prove value. This success can then be used to secure leadership support and expand adoption more broadly.
Why should you adopt a CI/CD model?
CI/CD facilitates a faster time to market. Automation streamlines parts of the process, while quicker error detection leads to less time putting out fires. Customer satisfaction can increase as well when you’re providing more regular updates and a positive user experience.
The incremental changes and automated integration of CI can improve the quality of code in each update. Reducing the instances of faulty code getting pushed to production significantly improves web application security and has countless positive business impacts.
When speed and accuracy increase, costs drop. Your CI server can run hundreds of tests within seconds, drastically cutting down on testing costs. You undoubtedly have competitors using CI/CD, and if you’re sticking with traditional models, you’ll be left behind.
How to get started with CI/CD at your organization
Transitioning to CI/CD is best done in phases. This allows developers to learn and adapt to process changes and ensures that the new process will be fully tested before its introduction to production systems.
To set yourself up for success with CI/CD, start with these steps:
- Move software from your developers’ machines—resolving any disparities—into a version control (VC) process, such as Git or SVN.
- Build local developer instances with Vagrant or a similar tool to allow for some local testing.
- Document your procedures for pushing code into VC and dealing with merge conflicts. Ensure your staff is properly trained.
- Migrate code from the VC process to your production box as needed.
Now that you’ve built a solid foundation on which to start your full CI/CD migration, you can move to the next phase:
- Add a staging server for devs to push to. This allows future QA tests before production.
- Choose a CI/CD tool, such as Jenkins, to automate the pushes from staging to production. You may choose to introduce basic linting at this time.
- Begin building in security with tools like Dynamic Application Security Testing (DAST), Runtime Application Self-Protection (RASP), automated QA testing, and any additional compilation steps (such as minimizing JavaScript, CSS, concatenating files, checking software sources for CVEs, etc.)
You now have a functional CI/CD process. Much of the security automation will be executed by software, but it’s essential that your developers have proper training on both software and processes.
Read more about CI/CD Security
Learn about Rapid7's Web Application Security Product