Jenkins - Jenkins is an open-source continuous integration server with 300+ plugins to support all kinds of software development
Vexor.io - Vexor is a fast and cheap cloud continuous integration service with per-minute billing.
Travis CI - Focus on writing code. Let Travis CI take care of running your tests and deploying your apps.
Codeship - Codeship is a fast and secure hosted Continuous Delivery platform that scales with your needs.
Buildbot - Python-based continuous integration testing framework
Octopus Deploy - Octopus is a friendly deployment automation tool for .NET developers.