Get in touch
A person reads all of these. There is no ticket queue and no response-time promise, which is the honest version of what a small project can offer.
- Email
Anything at all: a question, a correction, an account you cannot get into.
contact@nublabs.com - Report a mistake in a lesson
The fastest route, because it goes where the fixes are tracked. Lessons are generated from a curriculum registry, so a wrong explanation is usually wrong in one place and fixed once.
Open an issue - Privacy
What is collected and why, and the switch for what this site measures.
Privacy policy
What to include in a report
Four things make a lesson bug fixable in one pass rather than three:
- The address of the page, which names the lesson and the example.
- The step number, if the problem is at one step. The player keeps it in the address bar.
- What you expected the algorithm to do, and what it did instead.
- Your input, if you were running the lesson on your own values.
A disagreement about an explanation is as worth sending as a crash. The explanations are the part with no test that can catch them being misleading.
Before you write
Help answers the questions that arrive most often, from whether you need an account to what happens to progress you made without one, and about answers where the pictures come from and what is free. If a lesson looks wrong at a particular step, it is worth stepping back through it once: the run is the engine's own, so a surprise is often the algorithm doing something genuinely counterintuitive - which is the part worth knowing.