When Austin Post dropped “White Iverson” on his SoundCloud in early 2015, he was just another 19-year-old kid from Texas trying to scratch out a living in LA. What a difference a year makes. Mixing the spaciousness of trap with the anthemic heart of country and classic rock, his signature songs—which also include the 21 Savage collab “rockstar” and the chill Swae Lee team-up “Sunflower” (from Spider-Man: Into the Spider-Verse)—have become some of the biggest (and most totally unhurried) blockbusters of the late 2010s, ambassadors from a post-genre world where anything is fair game so long as it sounds good. That he grew up on emo is evident—it oozes in his melodies. Singing, rapping, guitar, whatever—Post is doing it, and taking his sweet time, too.