We know all about Leetcode and Codewars and how these tend to train developers in abstract problem solving, but I haven't met a website that presents you with a production bug for you to solve. I find that this would be a lot more beneficial to learn how to identify and solve problems. Personally, I think it would be even better to use them in interviews. What do you think? And is there already a project like this? Share with the class.
An example would be you're given a rails application that takes 2s to load up a page and you're asked to speed it up.
Or an node application where an API endpoint is returning undefined and you're required to figure out why.
I think this way you can see different solutions to your problem, if it's an optimization one, and you can even reference the problem when someone can't duplicate it locally.