Mac users reported a slew of issues earlier today, with non-Apple apps locking up, behaving sluggishly and failing to launch.

The issue appears to be related to Gatekeeper. Gatekeeper is Apple’s service that checks non-Apple apps to make sure they’re not malicious. It seems the Gatekeeper server was experiencing some kind of problem verifying apps, likely due to macOS Big Sur’s release and Apple’s overloaded servers.

Big Sur is one of the biggest updates to macOS since OS X was originally released. It’s the first macOS that will let users run iOS apps. As a result, there has been a lot of pent up demand for this update.

🤔 FYI, seems to be something going on with super sluggish app launching right now. It doesn’t seem to be just us. We are looking into it! https://t.co/RZduhcBwiX

— Panic (@panic) November 12, 2020

👍 This issue now appears to be resolved. Please enjoy our Nova and Transmit updates!

(And to the Apple engineers who undoubtedly just had one heck of a wild day: thank you for your service)

— Panic (@panic) November 12, 2020

Today’s issues may be an indication of Big Sur’s early popularity, but it’s still an embarrassing hiccup in Apple’s big launch.