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!

Setting Kernel.srand config.seed in your Rspec config will cause calls to ruby methods such as rand, shuffle, and sample to return the same element every time for a given seed. More here.