Thanks for the heads up. I've searched far and wide to find any sort of docs for the built in debugger. ruby-debug was incredibly easy to use. require 'debug' sets a breakpoint, but I cant figure out any way to interact with it.

I use pry, however I've found it's very unreliable for stepping into shoulda tests, and often it errors out. I haven't been able to find stable alternatives to the most common ruby-debug commands 'l', 'e', 'n' and 'c'.