Ruby on Rails - How can I run automated tests on a user-uploaded Ruby file?

I'm currently working on a Rails application (React frontend) that deals with students submitting zipped directories of Ruby projects. The files are stored through Paperclip and S3 on an Assessment model. Currently, in order to grade student submissions, I must download every student file and test with RSpec individually from the command line.

I've improved the workflow through writing a script (in Ruby) that will take a directory of Zips, grade them all at once, and store each individual RSpec output in a scores.txt file.

The goal is to allow students to upload their .zips through a portal, and have them be immediately and automatically tested with RSpec. Is there a way to do this?

I've done a lot of searching, and so far can only find advice on how to test live user input (similar to codecademy, or other sites with integrated IDEs).