Rails continuous integration with Semaphore

This post covers continuous integration for Rails and is part one of a series of posts that detail the services my team uses at work.

Continuous integration

Writing software is error prone and riddled with problems. This is often amplified when working in larger teams as you try to integrate each other's code. Continuous integration, or CI for short, is a development practice whereby team members integrate their work as frequently as possible; it is normally achieved by having software automate the running of a test suite.

At Stinkyink we needed to find an affordable private CI server. We initially setup Jenkins as our CI, but we found this difficult to setup and a burden to maintain - we wanted a hosted solution. First we looked at Travis CI, a big player in the Rails world, however at the time they didn't offer private repositories (good and free for Open Source). We finally settled on a service called Semaphore.


Semaphore is a hosted CI solution that links directly to your Github repositories. It automatically runs a build script, which you can customise, with every commit you push and branch you create. Our script runs things like db:test:prepare, rspec, etc..

For us, Semaphore offered private repositories at an affordable price with basic plans that handle 5 projects for $39/pm - compare that to Travis CI's base private package at $129/pm.

Getting notified of build failures is important and Semaphore fully supports this. By default this is via email but we have our notifications sent to HipChat (saving HipChat for a later post). It also supports Github's commit status API, which means you get build statuses directly in a Github pull request.

Semaphore also allows you to exercise automatic deployment for successful builds. This is something we haven't yet taken advantage of but I would very much like to in future. It allows you to deploy via Capistrano, Heroku, Cloud66 (something else we want to look at) or a generic deployment script (bash script run in the root of the application).


We have been rocking Semaphore for well over a year now, and have loved our experience so far. It's reasonably priced, fast, had very little issues, the creators are lovely folk and their UI is sexy to boot.

If you haven't already setup a CI server for your team, especially if your team is small, then I can highly recommend Semaphore. Even if you don't go with Semaphore I recommend running a CI server as it takes the integration headache away from your developers and ensures they're not distracted with having to remember to run a test suite.