Résumé : Mixed reality systems overlay real data with virtual information in orderto assist users in their current task. They generally combine several hardwarecomponents operating at different time scales, and software that has to cope withthese timing constraints. MIRELA, for MIxed REality LAnguage, is a frameworkaimed at modelling, analysing and implementing systems composed of sensors,processing units, shared memories and rendering loops, communicating ina well-defined manner and submitted to timing constraints.The framework is composed of (i) a language allowing a high level, and partiallyabstract, specification of a concurrent real–time system, (ii) the correspondingsemantics, which defines the translation of the system to concrete networks oftimed automata, (iii) a methodology for analysing various real-time properties,and (iv) an implementation strategy.We present here a summary of several of our papers about this framework, as wellas some recent extensions concerning probability and non–deterministic choices.