Ask HN: Who is using a self hosted analytics system?

I'm so used to SASS based solutions these days like Mixpanel, GA, Kiss Metrics, etc. But with everything happening over the last few years in regards to privacy and security I've been looking into self hosted.

Is anyone else considering the same? I know this is standard for companies like Amazon and Facebook, but what about everyone else?

If you are using a self hosted setup, what is it? Custom built, open source, etc?