ngrok is a crucial tool, but in order for it to work with rails you will need to add your ngrok domain to your hosts in your config file.
config.hosts << "your ngrok domain". This is something I always forget, so I wanted to create a reminder for myself and others here!
Kernel.srand config.seed in your Rspec config will cause calls to ruby methods such as
sample to return the same element every time for a given seed. More here.