Zenon “Zen” Castillo (born August 10, 2004), known professionally as 1oneam, is an American recording artist and record producer from Greendale, Wisconsin, located in Milwaukee County.

Rising to fame through platforms like SoundCloud, 1oneam is an emerging artist in the underground music scene, known for having dreamlike melodies with self-reflective lyrics. His sound often incorporates sounds of pluggnb and ethereal production, creating a unique, emotional vibe.