We propose a simple programming language, called Nemo, specific to the domain of multi-task real-time embedded systems, such as in robotic, automotive or avionics systems. It can be used to specify a set of resources with usage constraints, a set of tasks that consume them according to various modes, and applications sequencing the tasks. We obtain automatically an application-specific task handler that correctly manages the constraints (if there exists one), through a compilation-like process including a phase of discrete controller synthesis. This way, this formal technique contributes to the safety of the designed systems, while being encapsulated in a tool that makes it usable by end-users and application experts. Our approach is based on the synchronous modelling techniques, languages and tools.