When comparing Concourse CI vs GitLab CI, the Slant community recommends GitLab CI for most people. In the question“What are the best continuous integration tools?” GitLab CI is ranked 2nd while Concourse CI is ranked 13th. The most important reason people chose GitLab CI is:
All build setup are stored in .gitlab-ci.yml file, which is versioned and stored in the project. Like Travis do.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Local iteration
Debugging on remote build agents is a nightmare (especially without isolated builds). Concourse CI can be run locally. When there are problems with the pipeline definition, it can be run and debugged locally. That means it takes less time to find and fix problems.
Pro Flexible
Resources are to Concourse as plugins are to Jenkins. In other words, resources allow Concourse CI to do just about any work necessary in a build. But resources follow a "service provider interface" that makes them easy to build in any language (not just JVM languages) and have a clearly defined computing model, built for composition. Resources don't clutter UI or tax performance.
Pro Scalable, reproducible deployment
BOSH is an open source tool for release engineering, deployment, lifecycle management, and monitoring of distributed systems. Since Concourse CI is built on top of BOSH, Concourse can scale across many servers or be run in the Cloud.
Pro Isolated builds
Build isolation keeps workers "clean". There's no configuration drift of agents. Or flaky interactions between build jobs.
Pro Usable
Visual pipeline view makes it clear what the automation does. Simple navigation to logs makes it easy to understand what happened in a build.
Pro Simple
Concourse defines three primitives that, together, can express arbitrary features and pipelines.
Pro File based configuration
All build setup are stored in .gitlab-ci.yml file, which is versioned and stored in the project. Like Travis do.
Pro Free and open source
All of GitLab CI's code is open source and under the MIT license.
Pro Parallel builds lessen test times
Tests are parallelized across multiple machines in order to reduce test times considerably.
Pro Docker intergration
Good integration with Docker.
Pro Highly scalable
The tests of GitLab CI run parallel to each other and are distributed on different machines. Developers can add as many machines as they want or need, making GitLab CI highly scalable to the development team's needs.
Pro Quick setup for projects hosted on GitLab
Since it uses the GitLab API for setting up hooks, the setup of GitLab CI for projects hosted on GitLab can be done in one click.
Pro Kubernetes integration
Easy to test and deploy on Kubernetes.
Cons
Con Limited infrastructure options
The downside of building on BOSH is that a full, scalable deployment of Concourse CI requires AWS, vSphere, or OpenStack. If you don't already have these, any one of them can be a big effort to set up, just to get a build server running. Might not be a good fit for smaller teams.
Con Not lightweight
Not a lightweight solution, demanding and memory hungry.
Con Cost
Larger projects will need upgraded version
Con Security risks
Con Windows not supported
No Windows support, but it's possible to use a Bitnami stack.