Kamaal Williams was born Henry Williams on December 14, 1989, in Peckham, South London, to a Taiwanese mother and a British father who both worked as architects. He learned drums and percussion in primary school and played in the school band. His father introduced him to Miles Davis and John Coltrane, while the garage and grime of South London supplied the rest of his listening. After Dulwich College he studied music production at the Bermondsey Centre of Southwark College, where he learned to play keyboards. At 17 he started a band with the singer Katy B and the drummer Joshua McKenzie, and he left it after two years to make his own records.

He has worked under two names from the start. From 2011 he released house and broken beat music as Henry Wu, a name he has called his ethnic background: Stir Fry Beats (GorillaTech, 2012), an EP on Tenderlonious's London label 22a in 2014, WU15 with the producer K15 in 2015, and Good Morning Peckham (Rhythm Section International, 2015). The name Kamaal, which means "perfect," came the same year, when he converted to Islam, and he joined it to his father's surname. He has described Henry Wu as the DJ and producer and Kamaal Williams as the band. From 2017 to 2020 he hosted a monthly NTS Radio show as Henry Wu, and in 2020 he gathered his earlier work as Shades of Wu: The Anthology. In 2021 he and Fred again.. made the track "Homies."

His breakthrough came with the drummer Yussef Dayes as Yussef Kamaal. The two had known each other since the late 2000s and became a working band when they rehearsed Williams's solo material for a Boiler Room session. A 20-minute set at Gilles Peterson's Worldwide Awards in 2016 led to a deal with Peterson's Brownswood Recordings, which released their only studio album, Black Focus, on November 4, 2016. It was recorded at Quartermass Studios with Malcolm Catto producing, and the additional musicians were the saxophonist Shabaka Hutchings, the trumpeter Yelfris Valdes, the bassists Tom Driessler and Kareem Dayes and the guitarist Mansur Brown. AllMusic's Thom Jurek heard it as spiritual jazz-funk, broken beat and global sounds in one weave. The duo won the Breakthrough Act award at the 2017 Jazz FM Awards. Before a scheduled SXSW appearance in March 2017 they were refused entry to the United States after Dayes's visa was revoked under a new executive order, and on May 4, 2017 they announced that the original lineup would no longer perform together.

Williams then founded his own label, Black Focus Records. The Return (May 25, 2018) was built from recorded jam sessions with the bassist Pete Martin and McKenzie on drums, with Richard Samuels engineering and mixing over six months; Williams has said he made it in his mother's living room with one microphone. It entered the UK albums chart at No. 63, reached No. 1 on the UK Jazz and Blues chart and No. 3 on the Billboard Top Jazz Albums chart in the United States. A 12-inch, "New Heights (Visions of Aisha Malik)" backed with "Snitches Brew," followed, along with a mix for the !K7 DJ-Kicks series (November 2019) and a live album from the Dekmantel Festival (February 2020). Wu Hen (July 24, 2020) is the record he treats as the full statement of what he calls Wu Funk. Its guests were the arranger Miguel Atwood-Ferguson on strings, the saxophonist Quinn Mason, the drummer Greg Paul, the bassist Rick Leon James, the harpist Alina Bzhezhinska and the singer Lauren Faith on "Hold On." He finished it in lockdown in Morocco in April 2020, and it reached No. 2 on the UK Jazz and Blues chart and No. 15 on the Independent Albums chart.

Stings (September 27, 2023, Black Focus Records) came after he bought an upright piano during the pandemic and began composing on it. It was recorded in Los Angeles and Chicago in early 2022 with Atwood-Ferguson arranging. XLR8R described it as rooted in the South London jazz scene but reaching toward the impressionism of Debussy, with hip-hop and electronic beats underneath. A run of live and solo releases followed on his own label: the EP Everything in Its Right Place (2024), the solo piano recording Solo Piano (Live In Tokyo) (April 21, 2025), Live at Flesh and Bones Studios (April 14, 2026) and the seven-track Last Night In Paris (June 26, 2026).

Williams rejects the label jazz for his own music, calling it elitist, and his records are better described by the mix he names himself than by any single genre. He started as a house and broken beat producer, he has cited 1990s boom bap hip-hop and J Dilla, Jamiroquai and the UK garage duo Oxide and Neutrino alongside Roy Ayers and Donald Byrd, and he calls his own genre Wu Funk, a blend of jazz, hip-hop, R&B and electronic dance music. NPR's Piotr Orlov placed his keyboard writing in the line of post-Mwandishi Herbie Hancock, Bob James's "Nautilus" and the productions of J Dilla.

What ties him to jazz in practice is how the records are made. A former drummer, he plays Rhodes, Nord and Juno parts with a percussive, rhythm-first touch, and the studio albums grow out of long live jams that are edited down, with a band that improvises on the base of each song from night to night. Critics have been divided on the result. Orlov thought Black Focus undersold his abilities, while Clash's Kalia Ammar wrote that after the split from Dayes he struggled for a time to find his own sound without that drumming. On the jazz side are the Jazz FM award, the jazz chart placings of The Return and Wu Hen, the Brownswood connection and a long run of jazz-club and festival bookings.