Google has released a beta version of Bazel, the tool it uses internally to automate software builds and testing, under an open-source license. Bazel is similar to Ant and Maven, but it stands out because it supports a wide variety of programming languages, is extremely scalable and generates bit-exact builds.
Bazel supports Java, C++ and Objective-C and plans to support Go, but it won’t be a good tool for Python, PHP or JavaScript. Also, it currently runs only on Ubuntu Linux and OS X; Google is working on Windows support.
