This tool ships empty. It holds no questions and no material of its own — you load a content pack from your own device, it is read here in the browser, and it never leaves the device it is on.
Load a pack
A .drillpack.json file. Nothing is uploaded: the file is read by this page and kept in this browser’s own storage, on this device only.
Why it works this way
Material somebody else owns can be studied without ever being published. The machine is published; the material is yours and stays yours. Which also means two people with the same pack get the same drill, and nobody without it gets anything at all.
It needs a real web address to work — saved progress, offline use and a home-screen icon all depend on it. A file opened straight from a Files app has none of those, and on iOS will not run at all.
Making a pack
A pack is one JSON file: a list of sections, each with its reference text, and a list of questions tagged with the section they belong to. A question with an answer can be graded; one without is a recall prompt you mark yourself. The format is documented in docs/web/drill/README.md.
Where you are
Sections
The reference is always open, including for sections you have not reached. Only the graded test waits its turn — being locked out of a procedure you are carrying this for would be the one failure that matters.
Where am I weak?
A spread of questions across the sections you have actually worked, scored per section so you can see which ones have gone soft. It does not guess about sections you have not studied — a gap is reported as a gap, because a gap that looks like a zero gets you a confidently wrong answer about your own readiness.
The whole document
What this is
A study machine with no material in it. It reads a content pack from your own device and drills you on it: reference, recall practice, and a graded test that opens the next section when you pass it.
Never tell before you ask
No answer is in the page until you have asked for it. Not hidden, not collapsed, not greyed — absent. An answer you can reveal with a long press or find by zooming is an answer you have read, and then you have not recalled anything.
The same rule as the lights quiz in colregs, and for the same reason.
Two kinds of question
Recall prompts have no written answer. You answer from memory, then check yourself against the reference and mark it. Harder, and the better of the two for learning.
Graded questions have an answer, so they can be asked as multiple choice and marked objectively. The wrong options are drawn from the same section — which makes them the plausible confusions rather than obvious throwaways. That is what the test is built from, so the mark that opens the next section is earned rather than self-awarded.
Where the questions came from
Each question shows its source — the part, the subsection and the row — so any answer can be checked against the reference in one tap. A question whose answer is wrong is then findable rather than lurking.
Questions a pack marks as hand-written are shown as such, because they carry somebody’s reading of the material rather than a lift from it.
Your pack, and your progress
Offline
Checking…
A study aid, not the source. Where this and the document it was built from differ, the document is right and this is wrong — and where the document and whoever is responsible for the real procedure differ, they are right and the document is wrong.