Hacker creates banned book library inside a Wi-Fi smart light bulb

The Banned Book Library project turns an inexpensive Wi-Fi smart light bulb into a digital dead drop for censored literature. The hacker used a bulb sold with Tasmota firmware pre-installed, based on an ESP32C3 with 4MB flash memory. By overwriting the firmware with a custom web server, the bulb creates its own open Wi-Fi hotspot. When powered on, anyone within range can connect and browse a curated collection of banned books stored in the limited flash space. The hardware teardown revealed exposed GPIO pins (R: GPIO6, G: GPIO7, B: GPIO5, CW: GPIO3, WW: GPIO4), which could later be used to add a microSD card reader for expanded storage.

The inspiration came from Ben Brown's short story 'Library', where characters maintain a decentralized archive of lost works, and from Cory Doctorow's 'Unauthorized Bread' about avoiding cloud lock-in. The hacker initially considered modifying Tasmota but ended up writing a custom firmware flashed over-the-air (OTA) to avoid soldering. The bulb's mundane appearance makes it ideal for covert deployment in communities where access to certain books is restricted. This project demonstrates how off-the-shelf IoT hardware can be repurposed for privacy-respecting, censorship-resistant information sharing without relying on centralized services.