The best open source alternative to CircleCI is Harness. If that doesn't suit you, we've compiled a ranked list of other open source CircleCI alternatives to help you find a suitable replacement. Other interesting open source alternatives to CircleCI are: GitLab and Semaphore.
CircleCI alternatives are mainly CI/CD Platforms but may also be PaaS & Deployment Tools or Project Management Suites. Browse these if you want a narrower list of alternatives or looking for a specific functionality of CircleCI.
Streamline code delivery with an open-source CI/CD platform featuring Git integration, fast pipelines, and hosted development environments.

Harness Open Source is a comprehensive software delivery platform that empowers developers to streamline their entire development workflow. From code repositories to deployment, this open-source solution offers a centralized hub for managing your software projects.
Key features include:
Benefits:
Whether you're a small team or a large enterprise, Harness Open Source provides the scalable features needed to meet your software delivery demands while maintaining developer autonomy and efficiency.
Looking for open source alternatives to other popular services? Check out other posts in the alternatives series and openalternative.co, a directory of open source software with filters for tags and alternatives for easy browsing and discovery.
A comprehensive AI-powered DevSecOps platform that integrates development, security, and operations, streamlining software delivery and enhancing productivity.

GitLab is the leading AI-powered DevSecOps platform, designed to revolutionize software development from planning to production. By integrating essential tools and automating key processes, GitLab empowers teams to build, secure, and deploy software faster and more efficiently.
Key features include:
Main benefits:
GitLab serves over 30 million registered users and is trusted by more than 50% of Fortune 100 companies. Recognized as a Leader by Gartner and Forrester, GitLab offers a complete solution for organizations looking to streamline their DevSecOps processes and deliver software faster without sacrificing security or quality.
Continuous integration and delivery platform offering faster builds, lower costs, and maintenance-free operations. Cut build times dramatically while reducing CI/CD expenses by 50%.

Open source CI/CD platform designed to help development teams ship software faster with enhanced quality and security. Unlike traditional solutions, Semaphore offers a maintenance-free alternative to Jenkins with no plugin updates required and single installation for entire organizations.
Key performance benefits include dramatic build time reductions - teams report cutting builds from over 1 hour to just 10-12 minutes. The platform costs 50% less than GitHub Actions while delivering 2x faster performance, making it an economical choice for teams of all sizes.
Advanced features include:
The platform supports enterprise-grade scalability - Confluent successfully migrated 1,800 engineers from dozens of Jenkins installations to a single Semaphore instance. Free Enterprise tier available for small teams, with comprehensive documentation and local development support through Skaffold integration.