In this talk, I will introduce unicoap, a unified, high-level CoAP suite for the constrained IoT implemented in RIOT. unicoap unifies support for different transports and several CoAP features. Abstracting different CoAP transports is challenging: First, messaging properties, including reliability mechanisms and PDU formats, vary between transports Second, various protocol features influence or build on top of each other. unicoap seeks to overcome these challenges by separating protocol mechanisms and features into layers. This approach is nontrivial due to memory demands in a constrained environment and state management across layers. Our design emphasizes extensibility, ensuring adaptability to evolving requirements such as support for future CoAP transports. Our key contributions consist of a layered design abstracting transport and protocol features, a modular implementation in RIOT for low-end hardware and an evaluation of our implementation.