Reading unfamiliar code
By the end of today you can open a codebase you have never seen, find where it starts, follow one path of execution end to end, and describe what it does without having read every line.
YesterdayDays 1 to 10 gave you the vocabulary: values, control flow, functions, collections, errors, imports and history. Today you use all of it at once on somebody else's work.
TomorrowTomorrow you consolidate everything so far and answer your first architecture question.
Why this matters
This is the actual skill this whole curriculum is built around. Most engineering time is spent reading, and reading well is what lets you judge AI-generated code instead of accepting it.
- Entry points
- Tracing execution
- Reading strategy
- Questions to ask of code
Learn it
75 minCopy this into Claude or ChatGPT. It quizzes you before it explains anything, which is deliberate. The resources under it are how you check what it told you.
Today's Master Prompt
Free · sign inA prompt written for this day alone: your level, the exact scope, what to leave out, and an instruction to quiz you before it explains anything. Paste it into Claude or ChatGPT and it teaches you today's material.
Check it against something that is not a model
An assistant can be fluent and wrong, and on a topic you met today you will not catch it. These cover the same ground and were made by people who do this for a living, so they are what you hold the explanation up against. They are other people's work and we only link to them, so judge them for yourself.
3 hand-picked resources
Free · sign inVideos, official docs and articles covering the same ground, each opened and annotated by hand. They are what you check the assistant against on a day you cannot yet catch it being wrong.
Build it
45 minFind a small real Python project on GitHub, ideally under 500 lines. Without reading every line, write half a page answering: what does it do, where does it start, what is the main path through it, what does it assume about its input, and what would break first. Time-box it to thirty minutes.
Recall it
20 minAnswer out loud, reveal, then mark honestly whether you had it. That score is the only thing on this page you do not get to choose.
4 recall questions
Free · sign inQuestions you answer from memory, then grade yourself against the real answer. The score is carried into the mastery rating below it, so an honest miss cannot quietly become a tick.
Rate it
Completion and mastery are tracked separately. Be honest, because an inflated rating only means the concept resurfaces sooner.
Mastery tracking
Free · sign inRate yourself against five named criteria per concept. Completion and mastery are tracked separately, and anything you rate shakily comes back automatically on a spaced schedule.
Recap
- 01Find the entry point first; everything else hangs off it
- 02Read names and structure before bodies
- 03Follow one complete path instead of skimming everything
- 04A visible string is the cheapest way into unfamiliar code
Your progress
Free · sign inMark days complete, pick up where you left off across devices, and watch completion and mastery diverge. Free, and the account exists only so ninety days of work cannot vanish with a cleared browser.