Low-cost open hobbyist board pairing an ESP32 with a Qorvo DW3000 (DW3110) UWB transceiver — the accessible way to bring up two-way ranging and tag/anchor positioning experiments in the Arduino/ESP-IDF ecosystem. Open example firmware and an Arduino DW3000 library ship in the Makerfabs GitHub repo. A development/ranging board, not a turnkey sniffer; use it to learn the radio, characterise a scheme's parameters, or build a controllable peer for authorised testing.