In the Internet of Things (IoT), billions of devices are connected. Very often, these devices are programmed with the C programming language, mostly because of the limited hardware resources of such objects. However, C is error-prone, and software bugs make devices both unreliable and vulnerable to cyber-attacks. Several cases of massive cyber attacks using IoT devices are documented. Moreover, the IoT is more and more deployed in areas such as energy, transportation and health: it is of paramount importance such systems are reliable, safe and secure. The goal of the DESSUF project is the design, implementation, and the evaluation of the safety, security and ease-of-use of a new programming language for the IoT.