When comparing Semaphore CI vs Concourse CI, the Slant community recommends Semaphore CI for most people. In the question“What are the best continuous integration tools?” Semaphore CI is ranked 10th while Concourse CI is ranked 13th. The most important reason people chose Semaphore CI is:
Whenever a new push is made on GitHub or Bitbucket, Semaphore automatically runs tests on that branch.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Automatic Testing
Whenever a new push is made on GitHub or Bitbucket, Semaphore automatically runs tests on that branch.
Pro Free for open source
Semaphore supports open source and offers unlimited open source projects.
Pro Complete customer support
Semaphore offers all-around customer support for its commercial users.
Pro Free 100 builds per month for private projects
Semaphore offers 100 builds every month for private projects. This package is free for an unlimited time and offers: free & unlimited deploys, unlimited collaborators and running tests in parallel.
Pro GitHub integration
Projects can be imported from GitHub and Semaphore will automatically connect with that repository, once that's done, it will automatically trigger for every code commit.
Pro Docker support
Out of the box Docker support. Additionally, Semaphore can cache Docker images by using included docker-cache commands.
Pro Easy to configure
Semaphore is quite easy to configure and work with. It easily integrates with GitHub and a first build is only a few clicks away.
Semaphore is configured using .yaml configuration files which can be added from the web UI. There are a lot of tutorials out there that help developers configure Semaphore to their preference.
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.
Cons
Con Proprietary with private project for $30/month
Semaphore is not free and nor is it open source. Pricing starts at $29 per month. However, there is a free option for private projects which have less than 100 builds per month and it's free for open source projects.
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.