I was eager to try out the new rails support and disappointed to find that there doesn't seem to be a straightforward way to run shell commands, which are a big part of normal rails project workflow. I realized I could make do with ruby's syntax for executing system commands to generate new files etc. but as I created a new model, nothing changed in the file tree and I was unable to open the file to edit. This makes working on rails projects in repl.it really untenable except to upload an existing project to share.
I'm excited about the improvements and looking forward to more progress!