Hudson is a popular open source continuous integration server. It allows developers to automatically build and test code changes. Hudson can monitor projects that use Ant and Maven builds. It provides trends on test failures over time and failed builds are easy to identify. Hudson is useful for projects of any size from personal projects to those with hundreds of developers and thousands of tests.
![Hudson tanabata.trac](https://cdn-ak-scissors.b.st-hatena.com/image/square/d1b0373603bbce2d10a99d459782b2f311aa43a1/height=288;version=1;width=512/https%3A%2F%2Fcdn.slidesharecdn.com%2Fss_thumbnails%2Fhudson-tanabata-trac-100708081020-phpapp01-thumbnail.jpg%3Fwidth%3D640%26height%3D640%26fit%3Dbounds)