Interesting you should say that. I've recently cleaned up a big install of their Go product. What struck was the massive NIH-ness of it the product. I wondered if it mirrored the organization behind it. (And if you want to avoid the complexities of the likes of Jenkins, do yourself a favor and whip up a Python script instead. It'll look the same after a few years anyway.)
You should do some research. Go came from a product called Cruise, which in itself came from Cruise control. Search that name and you will know which tool came first and who was behind it. (Link just in case - https://en.m.wikipedia.org/wiki/CruiseControl )
Definitely not NIH. Many new tools in CI/CD space clearly acknowledge Go as the one of the first tools in the pipelines and CD area. While ConcourseCI looks good, even Jenkins 2.0 cannot compare to the first class pipelines support in Go.
I wouldn't have jobs fixing these installations if I hadn't worked in this area for a while. I used Cruise Control and lived to see it crushed under the dominance of Hudson/Jenkins. And Go bears very little resemblance to it. A classic second system, if you will. It's like how every new tool throws out everything old, aiming for a complete rewrite, but several years later is still a web interface where you enter shell commands. The opportunities for these to develop .. intricacies are endless.
If you think Go was the first tool in the CD area, that probably says more about Thoughtworks defining CD as whatever-we-say-it-is, rather that the capabilities of a specific tool. It's not that people didn't do CD before 2010. It didn't bring anything new at the time. I suspect Go would have fared better if it was a Jenkins visualization plugin, there it could have ridden the coattails of its DSL system. Jenkins is the PHP of CI/CD and you need to go above and beyond it if you want to replace it. I would love, for example, to see Ansible/Red Hat bring their automation experience to this space. Imagine a CD Tower plugin, or a build system where not just the dependecies are declarative. I haven't had the opportunity to use Concourse yet, but I'm sure I will.
I lived through the nightmare of cruise control. Kudos to Thoughtworks for writing it as it was the first CI tool, and then actual thanks to JetBrains for writing Team City so we could actually make sense of our builds!
