I'm also a big fan of
early repl.it. I used to be able to hit a bookmarked url and get a repl
right away. But its been getting slower and slower and more complicated lately, and this whole situation left a bad taste in my mouth, and it's probably the push I need to move to an alternative.
In case anybody is thinking of building -- I'd happily pay for a similar app that let's you write/share private repls, with third-party package support (yarn, pip, nuget, maven, etc.)