Kraken is down
status.kraken.com
status.kraken.com
But of course sustained rapid user growth without a robust preexisting scalability approach means you're caught with your pants down, and it's a struggle to put them back up, at least until new user traffic starts to die down.
Considering that only perhaps 10% of businesses take off, this isn't a bad approach but it does mean doing some catch-up in the event of success.
It can also be hard to predict exactly where scaling challenges will lie without having the scale traffic to inform you. That is, much time and effort can be expended solving non-problems that never appear.
There was no email or information before this "maintenance", and customers just blindly had to take an entire day of cryptos being unavailable to them.
[0]: https://www.reddit.com/r/Kraken/comments/7pjflh/psa_system_u...
https://www.reddit.com/r/Kraken/comments/7pjflh/psa_system_u...
Now however - after 6 hours - I'm starting to worry about my USD150. ;-)