DAÏVE HUD is a full-function Underwater Heads-Up Display (HUD) Dive Computer that transforms compatible framed dive masks into connected underwater computing devices. Its clip-on design allows divers to upgrade their preferred mask in seconds without switching to a dedicated smart mask. The full-color 0.23-inch MIPI OLED provides a 640×400 interface for depth, dive time, NDL, tank pressure, compass, temperature, and safety alerts, while underwater messaging enables diver-to-diver communication. Powered by an ESP32-P4 SoC with camera and display interfaces, DAÏVE is designed as an edge-AI-ready hardware platform for future computer vision, marine-life and environmental recognition, and AI-assisted analysis of dive and sensor data. A replaceable 14500 rechargeable battery provides up to 40 hours of runtime, and the system supports depths up to 120 meters.