I keep getting a "Backend offline. Please try again later" message and I noticed that the API calls are returning the 500 status. Both clearnet and Tor. DDoS maybe?
Exactly, the same here I have been trying to see the content and the features in the site before making proper Review on the site but the website both the onion and clearnet are not working instead one shows "The site can't be reached".👇

And second one (clearnet) shows pure blank page👇

With this we can't say anything about the site until the site works properly before people can make their honest review and comments. So make the site working for easy access and mixing with fair transactions.