At 12, Leniz began writing music; the Dutch drum-and-bass producer and DJ, whose real name is Querijn van Bijsterveldt, comes from Nijmegen. Before going solo, Querijn made drum and bass as one half of the duo Newcaise. The artist name came from “Le Nice”. An early solo release was the 2017 single A Journey / She Won't Wait on Detached Audio. His music has appeared on Liquicity, Differential, Fokuz Recordings and Soul Deep, as well as Galacy.
Leniz released the EP Love in Excess in 2020, followed by the album Perceptions of Reality on Differential Recordings. In discussing the album, Querijn named 1990s atmospheric jungle and early-2000s liquid drum and bass as influences, including Seba, Good Looking Records, Artificial Intelligence and TC1. The album features collaborations with Brainwork and Perspective Shift, with Brainwork joining Leniz on a track. Querijn also spoke of experimental collaborative work with Ivoryghost. Other releases include the EP Changing Tides, and the album Maze & Madness. Leniz and Humanature made the track “Querencia”; “Where Stars Don’t Matter” is another of his tracks.
In 2025, Leniz released the single Declare Peace Ep on Four Corners and the single “The Music” on Differential Recordings. That year also brought the single “Revelation” on Liquid V. Leniz and Telomic made “Fallen From Grace” for a charity compilation supporting Ukraine. In 2026, “Within Our Realms Vol 1” arrived as a Fokuz Recordings single with Dan Atlas, and “Gradually” came out as a single on Leniz Music. Fokuz Recordings.