37C3 Hub Digital Badges
Assembly-created digital achievement badges
The 37C3 Hub archived a digital badge system where assemblies could create badges that visitors might find, redeem, and display during the Hamburg Congress.
Tag dossier
Assembly
Badge records tagged with Assembly, across Germany, United States.
38C3 Hub Digital Badges
Expanded assembly-created Hub badge system
The 38C3 Hub archived an expanded digital badge system where assemblies created discoverable event badges for visitors, grouped into categories such as General, Exploration, and Help.
39C3 Hub Digital Badges
Assembly-created Hub achievement badges
The 39C3 info pages documented a Hub badge system where participants could collect assembly-created digital badges via redeem tokens, profile assignment, QR codes, and challenge or visit workflows.
Ouroboros Badge (DEF CON 34)
Independent CH32V003 bare-metal UART crypto-puzzle badge offered toward DEF CON 34
K Badges' maker-controlled Tindie listing identifies Ouroboros as a $29.99 bare-metal RISC-V-assembly electronic badge on a CH32V003, with a custom UART cryptographic puzzle, a 12-LED Charlieplexed matrix, a circular single-layer PCB with exposed traces, and a hand-soldered two-AA configuration. Its August 4, 2026 storefront snapshot is out of stock; the seller says a new order is coming and hopes to bring some to DEF CON, rather than confirming units, arrival, pickup, or delivery. In a first-person r/Defcon announcement, the maker says they created the project and links the Tindie page and a GitHub technical explainer, while separately offering to arrange a DEF CON pickup by email for Tindie buyers. The product also makes 115200-baud puzzle, cryptographic-framework, low-power, and performance statements, but neither the product nor the maker-linked generic AVR framework establishes a released matching CH32V003 firmware or hardware package. This is a source-backed independent pre-event maker offering, not an official DEF CON badge, registration credential, confirmed fulfillment, verified cryptographic implementation, hardware-safety record, or reusable-image source.