The document discusses the design of a simple hardware Bitcoin wallet called HWallet. It describes the components used, including an NXP K82 microcontroller, OLED display, and USB connectivity. It outlines the code layers including communication protocols, cryptography libraries, and a main processing loop. Expanding on the design, it proposes adding functionality for generating and deriving recovery seeds according to BIP standards, as well as integrating FIDO U2F for hardware authentication.