esp32-c3-adblock
Network-wide DNS ad blocker firmware for a cheap ESP32-C3 board
What it is
Firmware that turns an ESP32-C3 microcontroller, with no PSRAM, into a DNS sinkhole for your home network. Blocklists of up to about 537k domains are kept in flash as a sorted table of 40-bit hashes, and each query is binary-searched against it, with blocked names answered as 0.0.0.0 and all others forwarded upstream. A web dashboard shows stats, accepts custom blocks and blocklist uploads, and handles over-the-air firmware updates. Tinkerers who want Pi-hole-style blocking on a tiny board plugged into a router's USB port flash it once and manage it over WiFi.