As others have said, every other request is a 504 at the moment.

But for the platform itself-- pretty cool that you have file separations and visual renderings, going beyond simple code execution. I like it. I tried build something similar on algodaily.com a while back, but found that my audience wasn't that interested in creating tutorials.

Some feedback:

1) I wasn't immediately sure there were multiple steps at first.

2) Execution time is a bit slow.

3) I was monitoring the network calls and saw no requests when code executed -- are you doing this in the client? Just a heads up that there's some security vulnerabilities to be aware of.

4) The UI could use some polishing. Maybe look for a color palette that blends colors together better.

Congrats on shipping!