"Start with the free tier for a few build configs and see how it works for you, then according to your scale find the enterprise license which fits you the most."
CircleCI's continuous integration and delivery platform helps software teams rapidly release code with confidence by automating the build, test, and deploy process. CircleCI offers a modern software development platform that lets teams ramp quickly, scale easily, and build confidently every day.
TeamCity is a Continuous Integration and Deployment server that provides out-of-the-box continuous unit testing, code quality analysis, and early reporting on build problems. A simple installation process lets you deploy TeamCity and start improving your release management practices in a matter of minutes. TeamCity supports Java, .NET and Ruby development and integrates perfectly with major IDEs, version control systems, and issue tracking systems.
Easily sync your GitHub projects with Travis CI and you'll be testing your code in minutes. Travis CI for private repositories has plans for every size project. With Travis CI testing your open source project is 100% free.
