39C3 Hub Digital 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.
Chaos Communication Congress
39th Chaos Communication Congress
The December 27-30, 2025 Hamburg Chaos Communication Congress whose official info pages documented a Hub badge system for assembly-created digital souvenirs, challenge rewards, and help/exploration badges, alongside independently scoped Cyberwatch and Critical Decentralization Cluster electronic assembly badges.
Hamburg · Germany · 2025
39C3 Cyberwatch Badge
An electronic badge created for 39C3 as a modular, solderable watch-style device. The project was designed to be reconfigurable with interchangeable daughter boards (called shards) for different use cases.
39C3 Critical Decentralization Cluster Badge
The Critical Decentralization Cluster's CDC Badge was presented as an electronic conference badge and development board at the completed 39th Chaos Communication Congress. The source-backed open-hardware platform combines an ESP32-S3, TROPIC01 secure element, front-lit e-paper display, twelve-button keypad, LiPo power path, and expansion ports, while public sources do not establish a conference-wide or admission-badge allocation.
Lifecycle
Add-ons & Upgrades
39C3 Cyberwatch Badge
source-backed
LoRa shard path
Project documentation and README material link a LoRa expansion shard to an adapted Meshtastic path, indicating an explicit long-range radio capability target.
39C3 Critical Decentralization Cluster Badge
source-backed
Raspberry Pi, SAO, and Grove expansion surfaces
The public repository documents a Raspberry Pi GPIO header, a SAO port, and a Grove-compatible connector as three expansion paths. It does not establish that any particular add-on was distributed or supported at 39C3.
39C3 Critical Decentralization Cluster Badge
source-backed
ESP32-S3 and TROPIC01 secure-element core
The official 39C3 CDC Badge presentation and RIAT hardware repository identify an ESP32-S3 development platform paired with a TROPIC01 secure element. The catalogue does not treat that hardware description as a claim about every physical event unit's exact revision or configuration.
39C3 Cyberwatch Badge
source-backed
Modular watch architecture
The 39C3 Cyberwatch project is documented as a solderable watch-style base badge that is designed to accept interchangeable shard boards through a modular hardware concept.
39C3 Cyberwatch Badge
source-backed
SD-card shard interface
The project documentation describes an SD-card form-factor interface used to carry modular add-on boards in place of fixed accessory ports.
39C3 Cyberwatch Badge
needs completion
Firmware expectation context
Project sources indicate a base firmware expectation around congress time and a prebuilt firmware trail for shard use, but they do not confirm a complete public production release artifact set for all build variants.
39C3 Hub Digital Badges
source-backed
Assembly-created badge categories
The 39C3 documentation lists General, Explore, and Help categories for badges created by assemblies through the Hub backoffice.
39C3 Hub Digital Badges
source-backed
Profile visibility and management controls
The 39C3 page documents Hub profile display, pending badge acceptance, default visibility, per-badge visibility choices, and badge management controls.
39C3 Hub Digital Badges
source-backed
Redeem-token and QR workflow
The 39C3 page says assemblies could provide redeem tokens with URLs and QR codes so participants could collect badges through the Hub.
39C3 Critical Decentralization Cluster Badge
public release
Versioned KiCad and fabrication release trail
RIAT publishes KiCad hardware, printable cases, documentation, fabrication-generation material, and v1.0/v1.1 releases under CERN-OHL-P-2.0. This preserves a reproducibility trail without proving final event production parity or a recipient inventory.
39C3 Critical Decentralization Cluster Badge
pre-1.0 beta
CDC Badge OS public firmware trail
krim404's public GPL-3.0 CDC Badge OS describes an ESP-IDF/PlatformIO application stack with hardware-key, identity, plugin, and BLE capabilities, but labels itself pre-1.0 beta and warns of data loss on flashing. It is not a verified 39C3 deployment image.
39C3 Critical Decentralization Cluster Badge
source-backed
Front-lit e-paper display and twelve-button keypad
The official event page describes a front-lit e-paper display and twelve-button keypad; the public hardware repository associates the keypad with a TCA9535 I²C expander.
Operational history
Issues & Camp Impact
The official Congress sources call the CDC Badge an electronic conference badge and development board presented by the Critical Decentralization Cluster, but reviewed sources do not identify it as the official CCC Human badge, a general Congress admission credential, a ticket entitlement, a conference-wide handout, an event price, an allocation count, or a recipient ledger.
The record preserves the concrete 39C3 assembly artifact while not conflating a cluster badge with CCC's main credential or assuming every attendee received one.
The later public CDC Badge OS README states that flashing can wipe stored FIDO2/U2F credentials, TOTP seeds, password-vault entries, GPG keys, and PIN data; it calls the project a proof of concept/demonstrator and says not to use it as-is for production or security-critical deployments.
The record may describe the public software capability surface but does not endorse the firmware, vouch for its cryptography, privacy, data durability, or safety, or imply it was the software deployed at 39C3.
The recovered public page documents how 39C3 Hub badges worked but does not expose a stable post-event public catalogue of every created badge name in this pass.
The record preserves the system-level artifact without inventing individual badge names, counts, icons, or assembly-specific rewards.
The source describes badges created by assemblies, redeemed through tokens or manual assignment, and shown on Hub profiles, not physical or electronic admission badges.
The catalogue models this as an official digital/community badge workflow and avoids hardware claims.
The public CDC Badge OS repository was created after the December 2025 event and describes v1.0/v1.1 hardware, while the RIAT hardware repository links multiple possible firmware projects. The reviewed sources do not provide a signed 39C3 image, installed-version inventory, setup/recovery policy for event recipients, event-specific feature configuration, or a historical deployment release mapping.
Later firmware transparency is useful evidence, but the catalogue does not backdate it into a confirmed Congress software image or user-support commitment.
No 39C3 Cyberwatch badge image is published because the recovered public sources and documentation do not provide a complete reuse basis for an official reusable photograph, attribution, and processing notes.
The entry remains image-free rather than copying unknown-rights project media, generated previews, or social/press photos.
No 39C3 Critical Decentralization Cluster Badge image is published because the current public source trail has not been paired with a reusable original badge or artifact photo or official upstream raster render with source URL, license or permission basis, attribution, and processing notes.
The Germany record remains source-backed and image-free rather than copying source-page media, documentation screenshots, event photos, social media, placeholders, or generated approximations.
No 39C3 Hub badge image is published because no reusable badge artwork, icon set, or screenshot provenance has been cleared with source URL, license or permission basis, attribution, and processing notes.
The record stays image-free rather than copying Hub UI screenshots, logos, badge icons, event graphics, or generated approximations.
RIAT publishes versioned v1.0 and v1.1 hardware sources, KiCad fabrication material, cases, and documentation, but the reviewed public record does not map a specific release, component substitutions, test result, PCB lot, enclosure, battery, production quantity, factory/assembly path, or final configuration to each physical 39C3 unit.
Open hardware remains a preservation and reproduction trail without becoming a claim that every 39C3 badge exactly matches a current repository release or bill of materials.
The current source trail shows a complete project concept and extension design, but public recovery in this pass does not fully prove how broadly distributed Cyberwatch badges were or document a complete attendance-wide shipping ledger.
The dossier records what is sourced—badge architecture and shard concept—without over-claiming circulation or official distribution scope.
RIAT's firmware checklist says the BQ25895 default fast-charge current would damage the documented 1200 mAh bundled LiPo and directs firmware developers to lower it; it also covers USB charging-port detection, system-voltage configuration, shipping-mode power-off, and TROPIC01 sleep. The public record does not establish that all 39C3 units had those settings, a matching battery, protection validation, current/thermal testing, compliance review, or safe user configuration.
The catalogue surfaces the published operational caution without presenting the badge as electrically validated, safe to charge, or safe to flash under every firmware/configuration combination.
Sources mention expected base firmware and linked firmware material but do not establish a single canonical, fully documented OTA/app ecosystem for all shard variants in this source pass.
The software record stays tied to the published architecture and shard references instead of inventing an endpoint, app-store, or locked release stream model.
Resources
Critical Decentralization Cluster at 39C3
assembly retrospective · The cluster's own 39C3 page ties the CDC Badge repository to the completed December 27-30, 2025 Hamburg assembly context.
CDC Badge OS README
firmware status and safety documentation · The firmware README documents ESP-IDF/PlatformIO, FIDO2/WebAuthn, GPG/SSH, TOTP, password-vault, plugin, BLE, and data-loss/early-beta caveats.
CDC Badge open-hardware repository
hardware and documentation repository · RIAT's public CDC Badge source tree with KiCad hardware, printable cases, documentation, fabrication instructions, expansion descriptions, and linked firmware projects.
CDC Badge CERN-OHL-P-2.0 hardware license
hardware license · Public CERN Open Hardware Licence v2 Permissive source for the RIAT CDC Badge project, with third-party component attribution retained separately by the repository.
The CDC Badge: conference badge & devboard with TROPIC01 and ESP32-S3
official 39C3 assembly event · Primary official Congress event page explicitly calling the artifact an electronic conference badge and devboard, and naming its TROPIC01, ESP32-S3, e-paper, LiPo, keypad, and expansion surface.
39C3 Critical Decentralization Cluster assembly
official assembly page · Official 39C3 assembly page for the Critical Decentralization Cluster, which lists the CDC Badge presentation in its recorded assembly programme.
39C3 Badges and you
official badge workflow documentation · Official info page documenting participant badge collection, redeem tokens, profile display, assembly backoffice badge creation, badge categories, QR codes, and Hub visibility controls.
39C3 info pages
official event page · Official event info source for 39C3 POWER CYCLES in Hamburg, December 27-30, 2025, and the Hub navigation that includes Badges and you.
39C3 Cyberwatch project page
official project page · Primary 39C3 assembly project page documenting the Cyberwatch modular smartwatch concept.
CDC Badge OS source
post-event public firmware · Public GPL-3.0 firmware project for CDC Badge v1.0/v1.1 hardware. Its January-July 2026 public history is kept separate from an asserted 39C3 deployed image.
CDC Badge firmware configuration checklist
power and firmware caution · Source-published checklist covering BQ25895 charge-current/power settings, USB interaction, and TROPIC01 sleep requirements; it is not proof of configuration on every event unit.
39C3-release_board README
technical documentation · Raw repository README for the 39C3 release-board hardware and shard references.
Cyberwatch documentation
technical documentation · Project documentation covering the SD-card shard interface, shard-based hardware extension model, and configuration path.
CDC Badge v1.1 hardware release
versioned open-hardware release · Public v1.1 release evidence for the CDC Badge hardware tree. It does not identify which source revision, if any, was on a particular 39C3 physical unit.
Sources
39C3 Hub / Chaos Communication Congress: Critical Decentralization Cluster
Retrieved 2026-05-15 · Official assembly source that places the CDC Badge presentation in 39C3's cluster programme and describes the Critical Decentralization Cluster's event role.
39C3 Hub / Chaos Communication Congress: The CDC Badge: conference badge & devboard with TROPIC01 and ESP32-S3
Retrieved 2026-05-15 · Primary official Congress source identifying the CDC Badge as an electronic conference badge and devboard with TROPIC01, ESP32-S3, e-paper/frontlight, LiPo battery path, keypad, and expansion ports.
39th Chaos Communication Congress Infos: Badges and you
Retrieved 2026-05-15 · Primary official source for Hub digital badge collection, token redemption, profile management, assembly-created badges, categories, and backoffice workflow.
Chaos Communication Congress: 39C3 Cyberwatch project page
Retrieved 2026-05-15 · Primary official project page for the 39C3 Cyberwatch hardware concept and event context.
Chaos Communication Congress: 39th Chaos Communication Congress Infos
Retrieved 2026-05-15 · Official event source for 39C3 POWER CYCLES in Hamburg, December 27-30, 2025, and the Hub navigation surface.
Codeberg: 39C3-release_board repository
Retrieved 2026-05-15 · Primary repository source linked from project docs for CAD references, firmware, and supporting project assets.
Codeberg: Cyberwatch documentation
Retrieved 2026-05-15 · Public project documentation describing the modular shard concept and software/firmware build notes.
Codeberg: cyberwatch/39C3-release_board README
Retrieved 2026-05-15 · Raw public README describing hardware layout, SD-card sharding design, and branch of modular watch extensions.
Critical Decentralization Cluster: 39C3
Retrieved 2026-05-15 · Cluster-owned retrospective for the completed 39C3 assembly, its dates and location, and its direct CDC Badge repository link.
RIAT Institute / GitHub: CDC Badge hardware LICENSE
Retrieved 2026-05-15 · Primary CERN-OHL-P-2.0 license source for the CDC Badge hardware project; it does not automatically license every unrelated event mark or media asset.
RIAT Institute / GitHub: CDC Badge v1.1
Retrieved 2026-05-15 · Versioned public v1.1 CDC Badge release. It is source-release evidence, not a confirmed physical 39C3-unit firmware or bill-of-materials mapping.
RIAT Institute / GitHub: Firmware Checklist
Retrieved 2026-05-15 · Primary configuration-caution source for BQ25895 charging/power settings, USB interaction, full power-off, and TROPIC01 sleep handling.
RIAT Institute / GitHub: riatlabs/cdc-badge
Retrieved 2026-05-15 · Primary open-hardware source for the ESP32-S3/TROPIC01 board, e-paper/keypad/expansion design, KiCad fabrication material, linked firmware, and project-level licensing.
krim404 / GitHub: CDC Badge OS README
Retrieved 2026-05-15 · Primary public firmware-status source for the documented secure-element application surface and explicit early-beta/data-loss/security-critical-use warnings.
krim404 / GitHub: krim404/cdc-badge-os
Retrieved 2026-05-15 · Public post-event GPL-3.0 firmware source for CDC Badge v1.0/v1.1 hardware. Its later source availability is not treated as a 39C3 deployment ledger.