If you’re applying for a job in DevOps, you will likely be asked CICD interview questions. CICD, or CI/CD, is a popular DevOps workflow in modern tech organizations, so interviewers are interested in candidates who are familiar with how it works. If you want to advance your career in DevOps or computer programming, learning how to answer CICD interview questions is a great place to start.
CICD is a software engineering workflow combining Continuous Integration and Continuous Delivery.
CI, Continuous Integration, is the practice of frequently merging small changes to a software into the main codebase. Engineers working on a repository continuously merge their changes with the primary branch so that their code doesn’t conflict with any others. The more frequently the main branch is updated, the less likely it is that conflicts will occur.
CD, Continuous Delivery, is the software development practice of releasing incremental software updates frequently, rather than working towards large, significant changes. Its goal is to focus on small, quick releases, ensuring that the software is ready to be deployed at any time.
When these two practices are combined, CICD is a system of best practices that ensures code updates are tested, integrated, and delivered in an efficient and reliable way. When implemented correctly by development teams, CICD should enable better collaboration, better quality code, and more consistent updates. The CICD pipeline is often automated, allowing large teams to make sure a consistent standard is met with each update and deployment.
In this article, we will list some common CICD interview questions and provide example answers. As you prepare for your job search, you can use these sample responses to inspire your own answers. With strong answers prepared for these common CICD interview questions, you are sure to ace your next interview.
CICD, or Continuous Integration/Continuous Delivery, is a software development strategy that prioritizes small, frequent releases to a code base, ensuring continuous testing, reliable code quality, and reduced risk.
When a development team follows CICD best practices, they can ensure that updates are frequent, incremental, and safe. Small changes mean that each individual update to the codebase is less likely to cause large errors. Further, when a test suite is automated, the frequent integration means tests are run more frequently and efficiently. When implemented correctly, CICD is a great way to maintain code quality and ensure that the code is tested and updated often.
CT stands for Continuous Testing. It is the practice of establishing tests that run frequently and consistently throughout the DevOps pipeline, so bugs and conflicts are identified early.
CT should ensure a stable test environment, where automated tests provide constant feedback to the developers. This should help the development team to fix issues with the software long before it reaches any end-users. A strong testing program will include both frequent functionality tests for each update, as well as larger regression tests that look for errors in the full application. All tests should be passed before individual developers push their software updates to the main source code branch.
Continuous testing is an important part of a CICD strategy. Without automated tests ensuring that the software is stable and error-free, it can’t reliably be delivered consistently.
Version control, sometimes called source control, is the process of recording and managing changes to code over time. Software teams use version control software to keep track of what changes are made to a codebase, when they are made, and who made the changes.
Generally, updates to a codebase will be made on a separate “branch”, which will be merged with the main source code when the update is complete. Version control software will identify if there are conflicts between the source code and the updated branch.
When every update to a piece of code is recorded, it is easy for team members to verify what changes have been made with each update and, if necessary, restore older versions of the code.
Version control software allows different developers to work on individual updates to the source code at the same time. It keeps a history of all changes, so updates can be tracked and understood. It reduces conflicts in the code, and helps keep the codebase efficient and reliable.
A well observed version control program ensures that different programmers can make contributions to the source code without running into conflicts with changes made by other engineers, or by the same engineer on a different branch. When all team members use good version control practices, updates to a code base can be frequent and safe.
Version control is an important aspect of CICD. In order to ensure continuous integration, the changes made to any code must be carefully tracked and managed. The CI system must be integrated with the version control software so that changes can be recorded, conflicts can be identified, and tests can be run.
In previous roles, I used Bamboo, Atlassian’s CICD server, to automatically integrate and test changes to the source code. The team also used Jira and Hipchat, which integrate with Bamboo. We used Git for version control and Teamcity for automated continuous testing. For configuration, we used Puppet, and for feature flagging we used CloudBees.
In software, containerization is a type of virtualization in which an application and the dependencies and libraries required to run it are packaged together into a single container that can be executed in any computing environment. When the OS kernel and all the necessary libraries and dependencies are included in the container, anyone working on the application can work on it using only the container, without having to establish the right computing environment on a virtual machine.
Containers are portable, efficient, and secure, making containerization a great way for engineers to develop new code. Many DevOps teams use containerization when developing their applications, as it is efficient, consistent, and requires little operating system overhead.
Docker is an open-source containerization tool developed by Docker Inc. It is used by many DevOps teams to simplify development using containers that can be run in any computing environment. Docker makes containerization faster and easier.
While the details of a CICD pipeline will depend on the application, it is common for there to be four stages: Source, Build, Test, and Deploy.
Yes. In my experience Agile and CICD go hand-in-hand. Agile software development and CICD pipelines both aim to produce good, reliable software efficiently.
In an Agile framework, software is developed iteratively, with frequent changes, interactive collaboration with customers, frequent delivery. In previous roles, the DevOps teams I have worked with used CICD as a component of a larger Agile framework, collaborating to deliver reliable, testable code to customers at a consistent pace. Automation, continuous integration, and rapid feedback allowed us to keep our code reliable and our updates frequent.
When a DevOps team hosts their CI platform on premises, they have to manage and maintain the server themselves. This requires maintaining the hardware, provisioning resources, and handling server updates as necessary.
When using a cloud-based CICD platform, the DevOps team relies on the cloud provider to maintain the servers. They do not need to own, update, or install their own servers, and can instead perform continuous integration on the cloud platform.
The most important part of a CICD pipeline is automation. If I had to establish a CICD pipeline for a DevOps team, the first step would be to establish an automated testing suite that would run automatically every time new code is integrated. I might use Travis CI, Selenium, or Appium to establish a continuous testing regime, depending on the application.
If appropriate for the software, I would also start using Docker and containerization to make sure everyone on the team could easily work on the software in their own environment. This would be a quick way to get the whole team working efficiently.
I would try to establish a firm set of steps to go through for every code change. Ideally, most of these steps would be automated, but it’s still important to codify them so everyone on the team understands what the pipeline looks like.
Lastly, I would try to foster a culture of CICD throughout the team. While automated processes are integral, I also think it’s important to ensure everyone on the team is on board with these ideas. Continuous integration and deployment will be easier when everyone understands why it is important.
Before your interview, write down your answers to all of the most common CICD interview questions. You don’t need to memorize them word-for-word, but writing down your answers will help you remember the key points.
Then, practice saying these answers out loud. Use a mirror or camera to see what you look like as you say it. Your presentation is just as important as the words themselves. Practicing your answer to each CICD interview question will ensure you don’t stumble over your words when the actual interview comes.
Even if your interview is taking place online over a video chat, it’s important to look the part. Research online to see what the dress code is at the company, then dress accordingly. You might be overdressed compared to your interviewer, but that’s better than looking unprepared.
If your interview will be done remotely, make sure your camera and microphone are working, and there is good lighting in front of you so interviewers can see your face. You should also make sure there is nothing too messy in the background, or too personal. You may even have to move your laptop for the interview to ensure the background is appropriate.
If your interview will take place on the company premises, remember that the interview starts as soon as you get to the door. Before you enter the building, your outfit should be ready and you should be on your best behaviour. Greet anyone you see politely and appropriately, and treat them as if they are the ones giving your CICD interview. Everyone from the security guard to the secretary to the intern could be your future coworker, and it’s important to start off on a pleasant note.
While the example CICD interview questions in this list have focused on technical skills, your real interview will almost certainly include some behavioural questions. Behavioural questions are interview questions that seek to learn how you handle difficult workplace situations. They might include questions like:
The STAR method is a strategy for answering behavioural questions. STAR stands for Situation, Task, Action, Result, and it works like this:
By following these steps, you can structure your answer so that it showcases your competence and experience. With this format, you can create a compelling story out of your answer to any behavioural question.