Karpathy's nanochat: the missing-middle abstraction

Karpathy’s nanochat is the missing middle between llama.cpp (too low-level for most application work) and a full framework like LangChain (too much baked-in opinion for real engineering).

What I find useful about it - beyond the obvious pedagogical value - is that it commits to being production-ish without being production. It’s the right abstraction level for someone who wants to understand what an agent runtime actually does, without surrendering to a vendor-specific orchestrator.

The pattern is the same pattern Fulcrum is trying to hit from a different angle: give engineers a small, legible codebase they can extend, instead of a giant framework they have to accept. The 2026 hardware + software trajectory is going to reward this kind of middle-distance tooling more than it rewards either extreme.

Worth an afternoon even if you never use it directly.