Security Fest 2026 RP2040 Badge
Source-backed RP2040 LED-matrix conference badge
Security Fest 2026's public firmware repository identifies this as the official conference badge: a small, hackable RP2040 device with a 9×9 LED matrix, six buttons, USB surface, and public firmware. The official event site confirms the completed May 28-29 Gothenburg conference, while a contemporaneous attendee report credits Carl Vargklint's badge work. Allocation and delivery are not documented.