Look how far you’ve come.
Your CODEX learning record tracks practice, challenges, and progress privately on this device.
*Correct answer checks ÷ all answer checks. 0 attempts · 0 hints revealed. Rechecking a solved challenge also counts as an attempt.
Your practice rhythm
A small step, whenever you have a moment.
Milestones, not scoreboards
First spark
Complete your first lesson.
Curiosity in motion
Complete five lessons.
Across disciplines
Complete a lesson in every path.
Daily explorer
Practice on seven different days.
A second look can make it stick
Revision recommendations appear after incorrect attempts or using hints. Keep exploring!
Find your next lesson →Your learning, on your device
Lessons, answers, hints, and resume positions are saved in this browser’s local storage. There is no account or cloud sync. Clearing browser data removes your record. Export a readable copy anytime.
Offline caching is enabled in the published production app when the browser supports service workers. Open it online once to cache the app and its bundled lessons. The editor preview may not support offline installation.