Ask HN: What is your preferred stack for prototyping new apps?

I usually start with Sinatra (without a DB). Instead of an ORM & DB I'll create simple Ruby objects in memory. Maybe I'll have a Post class with an #all method. Similar to AR, but I'll hold off actually creating a DB.

As a prototype (I'll be throwing this code away) this approach works well enough to simulate how the real app might work. Mimicking some of the conventions I'll be using later makes the transition easier.

I avoid a CSS framework when prototyping. I might pull in jQuery if it's essential.

Rails. Plain old straight rails.

Rails + Zurb Foundation.

Middleman and Bootstrap