Mark Ryder, also known as Mark “Ruff” Ryder, is a UK garage and 2-step DJ and producer. He is associated with a number of musical projects and aliases, including Soundclash, Sonic Experience, Mutronix, Multicore, Masters of the Universe, The Dance Federation, Ruff Da Menace and Undercover Movement.

He is known for the track “Joy”, a rare vinyl release that becomes closely associated with the 2-step scene. The record uses the bass line and shuffle characteristic of the style, and its bass line is borrowed from the 1980s pop hit “Tainted Love”, giving the track a retro edge.