Beyond Compare - Beyond Compare allows you to compare files and folders.
Jenkins - Jenkins is an open-source continuous integration server with 300+ plugins to support all kinds of software development
WinMerge - WinMerge is an open source differencing and merging tool for Windows.
CircleCI - CircleCI gives web developers powerful Continuous Integration and Deployment with easy setup and maintenance.
Meld - What is Meld? Meld is a visual diff and merge tool targeted at developers.
Travis CI - Focus on writing code. Let Travis CI take care of running your tests and deploying your apps.