Chance The Rapper put on his free Teens In The Park (TIP) Festival for 13-24-year-olds at Chicago’s Northerly Island today. Chance’s buddy Donnie Trumpet was scheduled to headline, but of course Chance also came out to perform some of their collaborative album Surf, one of the best albums of the year. The part that was a surprise, though, was that Chance also brought out his other buddy Kendrick Lamar, who performed a brief set for the assembled teens and early twentysomethings. You can watch some fan-footage of Kendrick performing “m.A.A.d city” and “i” with Chance below, via Fake Shore Drive.

“m.A.A.d. city”:

Yo @chancetherapper just brought out Kendrick Lamar at TIP fest. Wow!

A video posted by Andrew Barber (@fakeshoredrive) on Jun 24, 2015 at 5:34pm PDT

“i”:

Kendrick came out of nowhere #TIPFEST @kendricklamar @chancetherapper pic.twitter.com/8fTEYHNddA

— *ALONE* THIS SUNDAY (@Provsounds) June 25, 2015

Thank you @chancetherapper, we appreciate you and all you do. He just threw a free festival and brought out Kendrick pic.twitter.com/rY0rCqiWaC

— Lyrical Lemonade (@LyricaLemonade) June 25, 2015

Not so long ago, Chance and Kendrick both made an unplanned appearance at Earth, Wind & Fire’s Bonnaroo set. If Chance and Kendrick making surprise appearances together is a thing that is just going to be happening now, it’s completely fine with me.