Bruno Sutic, "Async Ruby" - YouTube

Async Ruby is an exciting and innovating part of Ruby. It’s a new approach to concurrency best described as “threads with NONE of the downsides”. Async Ruby has mind-blowing capabilities, and is so good Matz invited the gem to the standard library. This talk is suitable for both beginners and experts, and is relevant for you if you’re making web requests in Ruby. It will introduce you to some the most impressive Async features and explain its core concepts.