How LLMs work
Next-token prediction, attention, training, and why models make things up
Turn the docs, papers and RFCs you need for work into short maps you play a few minutes at a time. Quick reviews bring each idea back before it fades.
Free and open source. Runs on your laptop. No account.
Made from RFC 6749 and RFC 7636
You saved the article, skimmed the doc, nodded through the talk. Then someone asks you to explain it. Learncroc is for the things you need to actually know for work.
New team
Paste them in and walk into your first design review knowing why the system works the way it does, not just where the files are.
The paper everyone cites
Play the map before the meeting, so you can join the argument instead of nodding along.
Before the review
Get the trade-offs straight before someone asks you to defend them.
Every part of a map comes from learning research, not from what looks busy.
Every stop opens with a question you can't answer yet. A wrong guess you cared about makes the answer stick.
Drag, sort, predict. Checkpoints test you on situations the cards never showed, because that's what work does.
What you've learned fades over days, then comes back in a five-minute review, timed by FSRS, the scheduler behind modern Anki.
This is stop 4 of the How LLMs work map. Guess first, play with it, then find out if you were right. The croc sits beside every stop: ask it to explain another way or go deeper. In a checkpoint it only gives hints.
How LLMs work, stop 4 of 11
Pick the one you'd bet on.
Learncroc is open source and runs on your own machine, so your company's docs stay where they are.
git clone https://github.com/learncroc/learncroc.git
cd learncroc
bun install
bun devNeeds Bun 1.2+. Then open localhost:5173.
Prefer Docker? Build the image from the Dockerfile in the repo.
No course to block out a weekend for. Play a stop while the build runs, and review in the time it takes to make a coffee.
Each stop is 2 to 4 minutes and under 500 words. A full map takes an evening.
No XP, no leaderboards, no nagging. Add a calendar reminder if you want one.
Relight without leaving the shell:
bunx learncroc relightExport your flashcards to CSV or Markdown whenever you like.
Made by hand, and they work with no AI key. A full map is eleven stops; a taster is a complete five-stop arc you can finish in twenty minutes.
Next-token prediction, attention, training, and why models make things up
Why a positive test usually isn't what it seems
See like a painter, and like a screen
Paste a link or the text itself and the croc finds the big ideas and turns them into a map of three, five or seven stops. It uses your own AI key, or a local model with Ollama.
A preview with sample docs. In the app, paste any link or text and the map is built from it.
Maps are plain YAML files you can keep in git next to the code. Our Claude Code skills turn your docs into a map, and learncroc lint checks it before you share it.
Learncroc is free and open source. You can read every line, run it at work and keep using it however things change.
The code is MIT. Our maps are CC BY-SA 4.0, so you can adapt them and share them on.
The app and every map we make stay open source. A hosted version will sell convenience, never learning features. If it works on your laptop today, it will never move behind a paywall.
No install, sync across your devices, our AI key. We're letting people in from a waitlist.
Join the waitlistStars help other people find it. Issues and new maps are welcome.