40-bit truncated FNV-1a (5 bytes/domain, ~0 collisions to ~500k) plus a custom partition table (drop OTA, ~2.8MB LittleFS). Combined StevenBlack + Hagezi Ultimate = 537,013 domains in 2.56MB flash, still ~40KB RAM. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>