One shared case every day · No account needed
Whydunit is a daily debugging game: hunt the bug, interrogate the mentor, raise your flag. Everyone gets the same case; your attempt and conversation stay private.
An incident report lands on your desk: the stack, the symptom, and a few red herrings to keep you honest.
A small codebase, generated fresh for your case. Every file is a suspect. Every line is a clue.
Work the case with a mentor who knows where the bug is buried — and won't just hand it over.
A daily debugging game. One shared case per UTC day, every day a new hidden bug planted in a small generated codebase. You hunt the bug, interrogate an AI mentor who knows where it is but won't hand it over, and raise a flag on the line you suspect.
No. The daily case is playable anonymously; your attempt and mentor conversation stay private. Create a free account to keep your case archive, build a public detective profile, and unlock custom cases.
Yes. The daily case is free forever, and a free account keeps your progress and archive. Pro adds 60 hunt credits per month.
The daily case is generated fresh each day with a hidden bug. Custom cases let you choose the challenge type (code bug hunt, devops outage, or security breach) and difficulty (Medium for a mid-level dev, Hard for a senior, Expert for staff-level). Free accounts get a limited number of trial custom hunts.
It is an AI that has analyzed your case's hidden bug and will guide your investigation through questions and hints pinned to evidence lines. It won't simply tell you the answer.
You point at the file and line you suspect. The judge returns correct, partial, or wrong. A correct flag closes the case; you can also give up and unlock a post-close review to study the code.
Free accounts can open today's and yesterday's daily. Older dailies require Pro.