Bug Hunts

Practice pages that each hide an exactly-stated number of planted bugs. Find them by hand or assert against the printed spec and watch it fail.

Every bug hunt

• Owlery Registration — 5 planted bugs
• Park Gate Log — 5 planted bugs
• Coffee Cart Checkout — 5 planted bugs
• Shuttle Booking Wizard — 4 planted bugs
• Council Election — 5 planted bugs

What a bug hunt is

The bug-hunt pages each hide an exactly-stated number of intentional bugs — defined as deviations from the spec printed on the page. Hunt manually or write assertions against the spec and watch them fail; the spoilers are gated behind a confirmation click, and your findings checklist is saved locally.

Single-technique practice instead

• All challenges
• Forms & Inputs (9)
• Waits & Dynamics (8)
• Mouse & Keyboard (6)
• Frames, Windows & DOM (7)
• Data & Files (3)
• Network & Auth (6)

Updated 2026-08-14

Fun UI Playground — all challenges, bug hunts, getting started, glossary, about.