GitLab vs GitHub CI: Understanding the Differences

Automation is everything in the modern software development world, with Continuous Integration (CI) helping make code testing, quality assurance and deployment processes easier for developers by allowing them to deliver quality software faster. GitLab CI and GitHub Actions (CI)—both integrated with leading source control management systems and providing all-in-one automation solutions for developers and teams—are among the most popular CI tools.

Introduction to GitLab CI and GitHub CI

Continuous Integration (CI) is a core practice of modern software development; it automates testing and deployment of code, enabling faster, more reliable delivery. Two of the most popular CI platforms are GitLab CI and GitHub Actions (CI). These tools integrate tightly with their corresponding version control platforms—GitLab and GitHub—allowing developers to easily automate workflows, test code, and deploy applications.

GitLab CI is a part of GitLab, which is a complete DevOps platform. You get everything from project planning and source code management to CI/CD features in it. It has some powerful CI/CD pipelines for testing and deploying your codes automatically. Along with that, Gitlab provides you some built-in security & monitoring tools., which surely makes it the best choice for those teams who want an all-in-one solution.

GitHub Actions on the other hand, is a flexible CI service from GitHub that lets developers easily build their own automation directly within the GitHub ecosystem. With GitHub Actions developers can create custom workflows to build, test, and deploy their code using GitHub’s community as well as its many integrations. It allows teams to automate their entire development flow all inside of their GitHub repositories.

Key Features of GitLab CI and GitHub CI

When comparing GitLab CI and GitHub Actions (CI), you need to realize what each platform's peculiarities are. Even though both are powerful automation and continuous integration tools, they have a different approach, customization level and additional features. Here is an overview of the major features of both platforms:

Key Features of GitLab CI

• GitLab CI has an inbuilt CI/CD pipeline. Automation can be done from code commit to deployment using this single platform.
• End-to-end DevOps solution is provided by GitLab, where we have multiple features along with CI/CD like project management, code versioning, monitoring and security tools. The complete development life cycle can be managed in a single tool by the teams.
• GitLab CI makes it easy to setup a pipeline with Auto DevOps that will automatically create a CI/CD pipeline, including configuring your projects kind (e.g. if it’s Node.js, PHP or whatever) of testing, building and deploys without having you write any custom script.
• GitLab CI has security scanning like Static Application Security Testing (SAST) and Dependency Scanning as part of the pipeline which in turn helps detect vulnerabilities during deployment itself
• GitLab CI provides a built-in container registry which can be used to build, store and deploy Docker images as a part of the CI/CD pipeline.
• Custom runners can be configured in GitLab CI and used to run jobs on any machine, making it possible to have more control over the build and testing environment.

Key Features of GitHub CI (GitHub Actions)

• GitHub Actions is an extremely powerful and flexible workflow automation tool. With it, you can create customized workflows that can be triggered by a variety of events (commit, pull request, etc), and execute actions (build, test deploy…) defined in YAML files.
• GitHub Actions marketplace has thousands of pre-built actions to use in a workflow. These actions range from simple things, like formatting code or building and publishing Maven artifacts, to much more complex actions, such as deploying previews or infrastructure.
• As Actions is a native feature of GitHub, it’s tightly integrated with other GitHub features like pull requests, issues, and code reviews. You can easily automate your GitHub workflow using actions.
• GitHub Actions have this concept called matrix build which can run your tests in multiple environments (For example different versions of a language or operating system) parallely, hence increasing the efficiency of the test run.
• GitHub Actions gives unlimited CI/CD minutes for open source repositories, thus making it an interesting tool to be used with your open source project. Developers can use this powerful automation tool without the fear of coming close to usage limits.
• GitHub Actions, like GitLab, also has support for self-hosted runners. Teams can run CI jobs within their own infrastructure with control over hardware and software.

Security Features in GitLab CI vs GitHub CI

GitLab CI has SAST (Static Application Security Testing) that you can use in any pipeline to check your code for vulnerabilities before it get executed. It also comes with an integrated DAST (Dynamic Application Security Testing) solution, which allows you to perform security testing of your running applications on URL level; this would be the level of vulnerability testing like SQL injection, cross-site scripting (XSS), etc. Dependency scan will help you checking if your third party component or library has any known vulnerability. You can easily integrate container scanning in GitLab CI/CD process and add visibility into a Docker image’s contents during continuous integration/continuous delivery pipeline. Apart from this, GitLab offers a consolidated security dashboard to manage and track vulnerabilities right from the same environment you apply patches with access control on feature-level as well on instance-level audit events provides near real-time information about user activities and system events in Audit Logs. Implement better data protection by applying access controls based on roles and job functions defined in GitLab — no additional cost required.

GitHub Actions has automated security alerts provided by Dependabot which scans and updates dependencies with known vulnerabilities, and creates a pull request for patch updates. It also provides Code scanning through CodeQL to check and find possible vulnerabilities in code based on patterns. The container security is further enhanced with the availability of GitHub Container Registry integration, as well as by integrating with third-party security products. The security dashboard gives visibility into vulnerabilities in a repository, while audit logs help provide visibility into user actions and changes to repositories. GitHub Actions also has fine grained permissions where you can control who can create, edit or even trigger workflows on your repository.

Performance and Speed Comparison: GitLab CI vs GitHub CI

GitLab CI is known for its scalability, especially in managing large and complex pipelines. GiLab provides several features to help improve the performance. You can run jobs in parallel, use shared runners which makes it very helpful when your projects has high volume. Gitlab auto scaling runner feature also allows you to scale up the number of runners automatically based on workloads so that your CI does not slow down during peak usage. Caching and artifact management provided by GitLab CI can also help reduce build times by reusing files or dependencies generated from previous builds.

On the other hand, GitHub Actions also provides strong performance features, particularly with its support for matrix builds. This allows developers to run tests across multiple environments simultaneously, which can significantly speed up testing cycles and reduce overall build times. GitHub Actions is optimized for performance with its ability to execute workflows quickly and efficiently, thanks to the platform’s robust infrastructure and global distribution. GitHub also offers concurrency controls and the ability to use self-hosted runners, which can be tailored to meet specific performance needs and handle high-demand scenarios effectively.

Conclusion

GitLab CI and GitHub Actions are both great CI tools, each with its own advantages. If you want everything available at your fingertips and in one place, choose GitLab CI. It has SAST, DAST, and container scanning, plus all the other DevOps functionality you could wish for. If you already do most of your development in GitHub—the issue tracker, the merge requests—then you'll prefer GitHub Actions hands down.