GrrCON 2024 · United States · 2024

GrrCON 2024 BadgeBuddy

Unofficial ESP8266 proximity-animation badge

BadgeBuddy was an unofficial GrrCON 2024 electronic badge built for roughly thirty friends, using an ESP8266 WiFi module, an 8x8 LED matrix, battery power, proximity scanning for other BadgeBuddy SSIDs, and a public code/wiring archive.

GrrCON GrrCon United States Grand Rapids Michigan Unofficial Badge ESP8266 WiFi LED Matrix BadgeBuddy North America

EventGrrCON 2024

SeriesGrrCON

LocationGrand Rapids, Michigan

CountryUnited States

People

Authors & Credits

badge builder and writeup author

CynicalSignals

Published the first-hand BadgeBuddy build writeup, GrrCON 2024 context, component notes, behavior description, and GitHub update.

Source

repository publisher

ickfosec

Published the public ESP8266 BadgeBuddy and Backpack of Shame source and wiring archive.

Source

Why It Mattered

It expands the North American compendium beyond official-conference badge programs into small-run hallway badgelife: a badge can be historically relevant when it maps the social graph of friends at a conference and leaves public firmware plus wiring evidence behind.

Hardware

The first-hand writeup lists an ESP8266 WiFi module, an 8x8 LED matrix, battery pack, headers, sockets, and a minimum parts plan for at least twenty badges with a stated per-badge cost. The public wiring diagram shows ESP8266 power and signal wiring to the LED matrix, and the published BadgeBuddy firmware uses data, clock, and chip-select pins 13, 14, and 15.

Software & Apps

The public BadgeBuddy firmware runs ESP8266 WiFi in AP+station mode, advertises the `BadgeBuddy` SSID, scans every 30 seconds for nearby BadgeBuddy BSSIDs, animates bouncing pixels on the 8x8 matrix based on unique badge count, and switches to a falling-code pattern when enough other badges are detected. A separate Backpack of Shame sketch runs an open `GrrCon WiFi` access point and increments a four-matrix scoreboard for unique connecting client MAC addresses.

Lore

CynicalSignals published the build writeup on October 2, 2024 and later added GitHub code and wiring diagrams on November 14, 2024. The project was explicitly a friend-group badge, useful as a conversation starter and rough nearby-friends indicator around the bar, restaurant, and convention center rather than an official admission credential.

Lifecycle

Add-ons & Upgrades

badge controller source-backed

ESP8266 BadgeBuddy core

The first-hand writeup and public firmware document an ESP8266 badge that advertises `BadgeBuddy` while scanning nearby WiFi networks.

Compatibility: GrrCON 2024 BadgeBuddy

Source

badge display source-backed

8x8 LED matrix animation

The badge used an 8x8 LED matrix for bouncing-pixel animation and a falling-code pattern once enough nearby BadgeBuddy networks were detected.

Compatibility: GrrCON 2024 BadgeBuddy

Source

build method source-backed

Header-and-socket construction

The component notes describe socketed LED matrices and ESP8266 modules, header-pin quantities, 3xAA battery testing, USB power as a fallback, and a stated USD 9.44 per-badge cost.

Compatibility: GrrCON 2024 BadgeBuddy

Source

companion conference device source-backed

Backpack of Shame companion

The same project archive includes a backpack-mounted open access point and four-matrix scoreboard that counted unique connecting clients during the conference.

Compatibility: GrrCON 2024 BadgeBuddy social experiment

Source

social badge behavior source-backed

WiFi proximity counter

BadgeBuddy counted unique nearby BadgeBuddy BSSIDs every 30 seconds and adjusted the animation density to reflect nearby badges.

Compatibility: GrrCON 2024 BadgeBuddy

Source

Operational history

Issues & Camp Impact

image-rights boundary note

The build post includes useful assembled-badge images and video, but this pass did not recover an explicit reusable image license, attribution basis, and processing provenance for catalogue publication.

The record remains image-free rather than copying blog photos, OpenGraph images, videos, screenshots, repository diagrams, generated art, or approximate badge artwork.

Confidence: local project policy
Status: needs licensed original replacement
Timeframe: current catalogue build
Source note: badge.gallery image policy and CynicalSignals BadgeBuddy writeup.

missing rights-cleared image note

No GrrCON 2024 BadgeBuddy 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 United States record remains source-backed and image-free rather than copying source-page media, documentation screenshots, event photos, social media, placeholders, or generated approximations.

Confidence: local project policy
Status: needs licensed original replacement
Timeframe: current catalogue build
Source note: badge.gallery image policy and CynicalSignals GrrCON 2024 BadgeBuddy writeup and public ickfosec/esp code and wiring archive.

repository-license caveat note

GitHub reported no detected license for `ickfosec/esp` in this pass.

The catalogue cites the repository as evidence but does not treat code, wiring diagrams, screenshots, or repository media as broadly reusable publication assets without explicit license coverage.

Confidence: GitHub metadata
Status: documented for source only
Timeframe: current catalogue build
Source note: GitHub repository metadata for ickfosec/esp.

unofficial distribution scope note

BadgeBuddy was built for roughly thirty friends attending GrrCON rather than issued as an official event-wide admission badge.

The compendium records it as unofficial badgelife and avoids implying GrrCON organizer publication, attendee-wide distribution, or admission-credential status.

Confidence: first-hand source
Status: documented
Timeframe: GrrCON 2024
Source note: CynicalSignals BadgeBuddy writeup and GrrCON official site.

Resources

Backpack of Shame firmware companion firmware source · Companion ESP8266 access-point and scoreboard sketch for the open `GrrCon WiFi` network and unique-client count display. BadgeBuddy firmware firmware source · Arduino-style ESP8266 firmware for the `BadgeBuddy` SSID, 30-second WiFi scans, unique-BSSID counting, 8x8 LED matrix animations, and falling-code mode. BadgeBuddy source tree badge source tree · Repository directory containing BadgeBuddy firmware and ESP8266 wiring diagrams. Building an Unofficial Badge for GrrCon 2024 project writeup · Primary first-hand build writeup for BadgeBuddy distribution scope, ESP8266 and LED-matrix hardware, proximity behavior, cost notes, battery test, backpack companion, and image-rights boundary. GrrCON official site official event site · Official event site used for GrrCON's Grand Rapids hacker, cybersecurity, and AI conference identity; it does not claim BadgeBuddy was an official event badge. ickfosec/esp repository source repository · Public repository containing the GrrCon 2024 BadgeBuddy and Backpack of Shame code and wiring diagrams; GitHub reported no detected repository license in this pass.

Sources

CynicalSignals: Building an Unofficial Badge for GrrCon 2024 Retrieved 2026-05-15 · Primary first-hand source proving BadgeBuddy's GrrCON 2024 context, unofficial friend-distribution scope of roughly thirty badges, component list, proximity behavior, backpack companion, and GitHub release trail. GitHub / ickfosec: ickfosec/esp Retrieved 2026-05-15 · Primary public source repository for BadgeBuddy and Backpack of Shame code plus wiring diagrams; GitHub reported no detected repository license in this pass. GitHub / ickfosec: BadgeBuddy.ino Retrieved 2026-05-15 · Primary firmware source for BadgeBuddy AP+station mode, SSID scanning, BSSID counting, LedControl display behavior, and animation thresholds. GitHub / ickfosec: BackpackofShame.ino Retrieved 2026-05-15 · Primary companion firmware source for the open GrrCON-themed access point, MAC-address tracking, and four-matrix scoreboard. GrrCON: GrrCON Cybersecurity and Artificial Intelligence Conference Retrieved 2026-05-15 · Official event source for GrrCON's conference identity and Grand Rapids context; no official-badge claim is derived from this page.