The current DJ scene is dominated by PCDJ controllers, which communicate with a PC via MIDI for performance. This eliminates the need to carry around equipment or vinyl records, making it easy to get started. However, many people who start easily quickly lose interest or realize the limits of their own talent. I am certainly one of them.

DJ controllers are equipped with multiple switches such as jog wheels, volume controls, and buttons, and can be purchased for just a few tens of thousands of yen. It's difficult to assemble a similar device yourself by gathering the necessary parts. This presentation will introduce examples of effectively utilizing DJ controllers as Human Interface Devices (HIDs).

I want to share the know-how of implementing each area in Ruby, from communication with the DJ controller to control of desktop applications and editors, and programming support.