Kendrick Lamar dropped a surprise new album earlier today.

Untitled unmastered., the follow-up to 2015’s world-winning To Pimp a Butterfly, appeared in the early hours with little warning besides a hint from Kendrick’s label Top Dawg Entertainment that they would be releasing something new this week.

Kendrick has been debuting unheard material during his appearances on late-night TV shows since 2014, with these tracks and verses making it onto untitled unmastered. The album features eight tracks, each detailing the date that they were recorded. Most date back to 2014, but some parts were seemingly recorded in 2013 and others as recently as this year. Incredibly, the album features production from hip hop legend Swizz Beatz’s son, who is just five years old. There’s even a video of him working in the studio.

Check out the album below.