apollo_upload_server-ruby VS Spree Commerce

Uploading files using a library built to support multi-part form through graphQL. Although this is pretty straightforward, it's not necessarily perfect as it is a privately maintained gem and doing uploads this way puts a lot of load on your server. https://github.com/jetruby/apollo_upload_server-ruby. This gem was built to mimic the file upload functionality of Apollo Server which is the popular Apollo server framework for node. This is likely the easiest solution to implement.

A good system to study is Spree https://github.com/spree/spree. It has an inventory and billing system and supports different adjustments and sale configurations. If you don't want to use it wholesale it's a solid Rails application that does most of what you want so you can use it as solid inspiration.

Spree Commerce: https://spreecommerce.org/

Maybe Spree?

I'd say Solidus and Spree are you best options rather than trying to roll out you own ecommerce solution.

When I was working on that company, that mobile ordering app, Counterless, I looked a lot at codebases like Spree, the Spree Commerce codebase. And that's how I learned a lot about how do you model an order with line items and things like that? I saw some amazing things that helped me develop an understanding and save a ton of time by looking at oh, they have a state machine. What are the ways that an order transitions through all these different states as it gets processed and charged? And how do you track all of those things?