Interesting approach to interactive learning. The form-based interaction is a nice middle ground between passive reading and open-ended chat.

One observation: the real challenge with "doom learning" products is retention. People install Duolingo with good intentions, then drop off. Consider adding: - Spaced repetition (show me this again tomorrow, then in 3 days) - Micro-commitments (5-minute sessions, not 30) - Contextual relevance (I just learned 'find' — now quiz me next time I'm actually in a terminal)

The quiz format works well for syntax/commands. For conceptual topics, maybe switch to "explain like I'm 5" mode with the LLM.

Good luck!