(cross-posted from a dup of this story...)<p>Although the move to the cedar stack introduced a lot of complexity, Heroku's flexibility is really starting to shine through - I've seen work on a smalltalk buildpack as well.<p>Long-term this trend is only going to accelerate, where we can assume an app-receptacle (lxc-containers, heroku's 'app', etc.) is setup properly out of the box. There are almost no downsides to this when executed well on the provider's side, and infinite upsides.