Leveraging 3rd party/OSS tools in a VSTS/TFS environment

In light of the recent TFS vs. OSS debates, I wanted to share how we are using both TFS and OSS tools to work with each other. Speaking as someone who has implemented (and extended!) TFS in a production environment since the early Beta 2 days and am currently using the VSTS/TFS stack, I can say that there is quite a bit of pain involved. But some of that can be alleviated by utilizing both commercial and OSS tools *with* TFS. Here are a few examples of how I (and some of our team) are "filling in the gaps" to make TFS and VSTS a little easier to work with.