I'm using Docker + Fig. The nice thing is that you can exactly replicate your production environment on your local machine and the Dockerfile syntax is really simple. The not so nice thing is that there's no "simple" way to run docker containers on multiple physical/virtual machines right now (that should become easier once Docker team releases their cluster solution). It would be nice to have a fig registry where people can publish complete Docker based systems (e.g. varnish + nginx + Node.js server) but I don't think there is such thing available at the moment. I wrote a bit about that idea here: http://syskall.com/crazy-and-not-so-crazy-startup-ideas-2015...

Also, I asked a similar question on HN one month ago and got some interesting replies: https://news.ycombinator.com/item?id=8805952