Flashcards.
Active recall on the ideas that matter — scheduled by an SM-2 algorithm so each card comes back right before you'd forget it. Grade yourself; the harder ones return sooner. Progress saves in your browser.
The Agent Loop & Harness
Plan-act-observe, tool calling, context management — the runtime behind every AI agent.
Transformers & Attention
Tokens, attention, and the architecture under every modern LLM.
System Design Foundations
Caching, scaling, consistency — the load-bearing ideas of every large system.
LLM Engineering
Decoding, RAG, evals, and cost — building reliable products on top of models.
How it works: each card gets an ease score. Rate a card Again / Hard / Good / Easy and the scheduler picks when you'll see it next — failed cards return tomorrow, easy ones drift weeks out. Come back daily and the deck teaches itself. Pairs with your daily streak.