Joseph William Quinn Walker (born 11 October 1988) is an Australian musician, singer, and producer who is best known as being the lead guitarist for the band King Gizzard & the Lizard Wizard.

Walker continued working with Trumpdisco for a number of years, beginning to be less involved around 2013[6] following the success of King Gizzard before fully leaving the duo around 2016.

King Gizzard grew in popularity following the release of their 2nd EP, Willoughby's Beach in 2011 and debut album, 12 Bar Bruise in 2012 on their own independent label Flightless Records.

[10] On 13 August 2019, King Gizzard released a game on their website to promote their upcoming album, Infest the Rats' Nest.

The album was recorded by Walker in 2018 using "a demo version of Reason and an Ableton crack", stating in a press release "I couldn't save any sessions out which forced me to finish each track on the spot.

"[2] Matija Zivkovic of X-Press Magazine would give the album a 7/10, stating "Overall, this isn't an essential release but it's also highly listenable, eclectic and fun.

With a slightly more pared-back approach and a non-cracked version of Ableton, Bullant could prove a great electronic diversion from the largely guitar-driven Flightless Records stable.

"[12] Cole Costello of Cosmic Magazine would say "Given his contributions to Gizzard, one might have expected heartfelt lyrics, blazing guitar lines, and magical melodies.

Perhaps he's simply saving that kind of material for King Gizzard – a group which, with exception of more left of center excursions like these – his commitment remains total...

"[13] On 2 July 2020, Bullant released an EP under PHC Films rather than Flightless called German People featuring artwork by Amy Taylor of Amyl and the Sniffers.