Joshua Howard Luellen (born February 2, 1989),[1] known professionally as Southside (also known as Sizzle), is an American record producer, rapper and songwriter.

[2] After meeting hometown rapper Waka Flocka Flame, Luellen signed with his record label Brick Squad Monopoly—an imprint of Gucci Mane's 1017 Records—as in-house talent in 2010.

Luellen and labelmate, fellow producer Lex Luger established the production team 808 Mafia that same year; it was credited on several commercially successful releases throughout the remaining decade.

[3] As a lead artist, Luellen signed with Epic Records to release his collaborative album with G Herbo, Swervo (2018), which peaked at number 15 on the Billboard 200.

Monster standout "Commas" was released as a commercial single in March 2015 and spent 20 weeks on the Billboard Hot 100 chart, peaking at number 55 while earning a gold certification by the RIAA.

Luellen is known for his dark, belligerent, and menacing hip hop sound coupled with hard hitting 808 kicks, crisp snare drums, fast hi-hats, frantic synthesizers, sinister lead instruments, and colorfully layered ominous orchestration of synthesized brass, hits, stringed, woodwind, and keyboard instruments.

He also uses his team tag, 808 Mafia and more recently, a sample of the Ironside (1967 TV series) theme song produced by Quincy Jones.

[5] He cites Lil Jon as his favorite producer and enjoys the production work made by Pharrell, Shawty Redd, and Drumma Boy.

[15] Inside the studio, Southside is known for his strong work ethic and strategic marketing acumen when producing beats for artists and getting the finalized track on the mixtape circuit or radio.