What is CI/CD?
Continuous Integration (CI) is the process of merging code changes from multiple developers into a shared repository and running automated tests and checks to ensure that the code is error-free and meets quality standards. CI helps to detect bugs early, avoid conflicts, and maintain a consistent codebase.
Continuous Delivery (CD) is the process of delivering the code changes to a staging or production environment, where users or customers can test them. CD ensures that the code is always ready to be deployed and that the feedback loop between developers and users is short and frequent.
Continuous Deployment (CD) is an extension of Continuous Delivery, where the code changes are automatically deployed to the production environment without human intervention as long as they pass the automated tests and checks. Continuous Deployment enables faster and more reliable delivery of features and fixes, and it also requires a high level of confidence in the code quality and the testing process.
Figure 1: CI/CD pipeline
The evolution of CI/CD tools for modern software delivery
According to Gartner, adopting cloud-native applications will skyrocket in the next few years, reaching 95% of all new applications by 2025.
Cloud-native applications are designed to run on distributed and scalable cloud platforms, leveraging microservices, containers, and orchestration tools. They offer many benefits, such as faster development, higher availability, and lower operational overhead.
CI/CD tools have evolved to enable cloud-native and serverless pipelines, reducing the cost of provisioning and maintaining servers. They also support infrastructure as code (IaC), which allows developers to define and automate the creation of cloud environments in a consistent and repeatable way.
Tools and platforms to implement CI/CD
Some of the most popular ones are:
AWS CodePipeline: AWS CodePipeline allows you to integrate various AWS services and third-party tools into your release process. For example, you can use AWS CodeCommit, AWS CodeBuild, AWS CodeDeploy, AWS Lambda, Amazon S3, ECS Fargate, ECR, and Amazon EC2 as stages in your pipeline. You can also use tools like GitHub, Jenkins, Chef, Puppet, and Ansible to complement your AWS resources.
Figure 2: Automate microservices deployment using AWS CodePipeline with the steps required to build, test, and deploy Docker images from a source repository to an ECS Fargate or instances in the deployment group.
GitHub: GitHub is a platform for hosting and collaborating on code repositories using Git, a version control system. GitHub also offers GitHub Actions, a feature that allows you to create workflows for automating tasks such as testing, building, deploying, and releasing your code. GitHub Actions can be triggered by push or pull requests, releases, or schedules and run on GitHub-hosted runners or your self-hosted runners. You can also use GitHub Marketplace to find and install third-party actions for various purposes.
Azure Pipelines: Azure Pipelines is a cloud-based service that provides continuous integration and continuous delivery (CI/CD) for any platform. Whether you use C#, Java, .Net, Python, Ruby, or any other language or platform, you can build, test, and deploy your code to any cloud provider or on-premises server. Azure Pipelines supports running your workflows on Linux, macOS, and Windows machines and deploying containers to individual hosts or Kubernetes clusters.
Jenkins: Jenkins is an open-source tool for automating various stages of the software development lifecycle. Jenkins allows you to create pipelines for defining the steps and stages of your CI/CD process and can run them on distributed agents or nodes. Jenkins can be installed on your own server or cloud platform and can integrate with various tools and services such as Git, Maven, Docker, Kubernetes, AWS, Azure, etc. You can also use Jenkins Plugins to extend the functionality of Jenkins and integrate it with other tools.
Figure 3: You can deploy Jenkins Controller / Agents on your servers or the cloud and run them on distributed agents or nodes that support various operating systems and containers.
Bitbucket Pipelines: Bitbucket Pipelines lets you build powerful, automated workflows for your code. With Bitbucket Pipelines, you can run tests, deploy applications, and monitor performance within Bitbucket Cloud. Bitbucket Pipelines integrates seamlessly with your existing tools and services, such as AWS, Docker, Jira, and Slack. You can customize your pipelines with YAML configuration files and use variables, triggers, and conditions to control your workflow.
GitLab: GitLab CI/CD is a powerful tool that allows you to automate the entire software development lifecycle. With GitLab CI/CD, you can create pipelines that run tests, build artifacts, deploy applications, and monitor performance. You can also integrate with external services and tools, such as Kubernetes, Docker, AWS, and Slack. GitLab CI/CD is based on a configuration file called .gitlab-ci.yml, where you define the stages, jobs, and scripts that make up your pipeline. You can also use variables, environments, triggers, and rules to customize your pipeline according to your needs. GitLab CI/CD is designed to be fast, scalable, and secure. You can run your pipelines on shared or dedicated runners or on your own infrastructure. You can also use GitLab’s built-in security features, such as secret variables, protected branches, and merge request approvals.
TeamCity: TeamCity CI/CD is a powerful and flexible tool for continuously integrating and delivering software projects. It supports a wide range of languages, platforms, and technologies and integrates seamlessly with popular tools and services. TeamCity CI/CD allows you to automate and monitor your entire software development lifecycle, from code changes to testing, deployment, and feedback. You can configure your pipelines using code or a user-friendly interface and run them on any agent or cloud provider. TeamCity CI/CD also provides advanced features, such as parallel and distributed builds, smart triggers, dependency management, code quality analysis, and more.
Buddy: Buddy is a minimal-friction automation platform that makes DevOps easy for developers, designers, and QA teams. It integrates with popular tools like GitHub, Bitbucket, AWS, Azure, Google Cloud, and more. With Buddy, you can create and manage delivery pipelines with drag and drop actions in a fully visualized UI.
Buildbot: Buildbot is a flexible and scalable tool that can handle complex projects and environments. It uses a task scheduling system that runs the work and produces the test report when any resources are available. It also has a master-worker system, where the master monitors changes and communicates information to the user or developer. Buildbot is suitable for continuous integration, testing, and delivery.
IBM UrbanCode: IBM UrbanCode is a powerful tool that enables you to deploy your applications across different platforms and environments. It gives you clear visibility into what is deployed, where it is done, and who is doing it. UrbanCode also supports server virtualization and connects with middleware projects easily. UrbanCode works well with Jenkins to build a pipeline that includes automated unit testing, code coverage, and code review.
Perforce Helix: Perforce Helix is a reliable, secure tool that helps you manage your code and assets. It quickly detects any threat, assesses risk, and determines the effects of that risk. Perforce Helix also supports collaboration and version control for large-scale projects. Perforce Helix integrates with Jenkins to add speed and a single source of truth to your CI/CD pipeline.
CircleCI: CircleCI is a fast and efficient tool that runs your pipelines on cloud or on-premise servers. It has advanced caching, docker layer caching, and resource classes for running on faster servers that can be set to run very complex pipelines quickly. CircleCI also integrates with many other tools and services to streamline your workflow.
CloudBees CodeShip: CloudBees CodeShip is a SaaS solution that helps you build, test, and deploy your web applications and serverless systems. You can customize your pipelines and automate your tasks with Codeship. Codeship also offers parallel testing, debugging tools, and notifications.
GoCD: GoCD is an open-source Continuous Integration and Continuous Delivery system that supports modern infrastructure and integrates with many external tools and services via its extensible plugin architecture.
Travis CI: Travis CI provides continuous integration and deployment for projects hosted on GitHub and other platforms. It supports multiple languages, environments, and platforms. Travis CI offers a simple YAML configuration file to control the build process.
Conclusion
CI/CD is a set of practices that enables companies to enhance the software development process and deliver high-quality software faster and more efficiently. CI/CD can help achieve business goals by ensuring that code is always deployable and ready to deliver value. By adopting CI/CD, companies can enjoy improved code quality, faster delivery, better collaboration, and higher employee and customer satisfaction.