I’m delighted to announce that Justin Kan and Aaron Harris are joining Y Combinator as Partners.

Justin was in the very first YC batch with me in the summer of 2005, and has been a part-time partner since 2011. Justin founded Kiko, Justin.tv/Twitch.tv, Socialcam, and Exec. He took the “do what it takes” directive of startups unusually far with Justin.tv, when he wore a webcam on his head and broadcast his entire life for 8 months, 24 hours a day.

For some time now, Justin has been who we send startups to with questions about growth and marketing. But he knows a ton about nearly every part of startups.

Aaron was in the YC Winter 2011 batch doing Tutorspree, which moved back to New York after their batch. He’s actually been a partner since October 2013—sometimes it takes us a while to get around to announcing things.

Aaron will also advise startups on all topics, but he’s especially good with anything related to finance.

We’re all very happy to have both of them on the team.