Hackaday Supercon

Sandbox Systems

Talk: Hardware for Emergent Games · Hackaday Supercon 2025

From Conway's Game of Life to cyberpunk bounty hunting in the desert, this talk is for anyone building interactive objects for crowds: badges, festival games, LARP props, or open platforms you expect strangers to extend.

The Alleycat loop stays simple on purpose. Hunters track Bounties through Neotropolis. When they meet, they jack PDN units together, a countdown runs, and the first button press after Go wins. Color coding, automatic scoring, and anti-button-mashing logic keep disputes off the table. At Neotropolis 2025, 328 active players logged 3,767 Quickdraw matches over three days. The hardware enforces fairness; the LARP supplies the story.

Tech touched in the talk: ESP32, OLED + haptic feedback, WiFi score reporting, serial-over-audio jack between nodes

Design Principles

These are the Sandbox Systems principles Elli shared on stage, useful whether you are building for fifty people or five hundred.

People before tech

Make the experience as simple as possible so players can put their own spin on it. Neotropolis is a role-play event; the PDN should enable character, not dictate it.

Opportunities over demands

Give players hooks, not scripts. Hunters must deliver a Declaration of Intent to Seize when they encounter a Bounty, but the catchphrase is entirely theirs. Structure creates drama; freedom creates stories.

Embed the rules in hardware

The Data Node decides winner and loser, uploads results automatically, and enforces timing rules players never have to memorize. Nobody breaks flow to check a rulebook or swap tokens. If your game needs a referee, ask what the device could adjudicate instead.

Sell the story with the tech

"The doodad", pure LED greebles with no gameplay function, exists because it looks like cyberpunk gear. Fiction and hardware should reinforce each other even when the blinkenlights are not load-bearing.

Design for accessibility

Cyberpunk-styled closed captioning on the intake film started as an accessibility feature and became an aesthetic everyone enjoys, the curb-cut effect in practice. Accessible defaults often improve the experience for the whole crowd.

Emergent Play

The best Alleycat moments were never prescribed. Players invent alliances, house rules for losses, and personal rituals around the jack-in. The PDN is a sandbox: open-source hardware and firmware intended for other makers to fork, extend, and argue with in their own events.

The full talk is below.