You can check Juni. (juni.co). They are mostly EU focused now, but can connect to US payment systems - just in case you want to offer cards to affiliates. Source: about 3 years ago

This is pretty much `assembly language the game`: https://tomorrowcorporation.com/humanresourcemachine It's not a useful architecture, but it teaches the thought process really well, and you end up discovering a lot of optimization naturally. - Source: Hacker News / 12 months ago

Other options have been given in this thread and I'd agree that for this particular situation the Tomorrow Corporation's "Human Resource Machine" is probably the best match. It's a constrained environment in a game that scales up to introduce this and more. Source: about 1 year ago

Not sure if 7 is old enough, I made this card "game" with my daughter when she was 10: https://punkx.org/4917/ which is not really a game but more like a puzzle, you have 54 small programs for a 4 bit made up computer (Richard Buckland's computer) and you have to interpret them in your head or with pen and paper. It's quite interesting to play with her when I change few instructions on a card. Other interesting... - Source: Hacker News / about 1 year ago

We have programming based games like Human Resource Machine and Hacknet. Source: over 1 year ago

The game us actually called Human Resource Machine and it is excellent. I've beaten that one and its sequel. But some people might find it difficult and I would say somebody in the lower grades definitely would. Source: over 1 year ago