A system and approach for deriving data for a constrained environment of a controller such as, for example, an embedded device. The controller may incorporate a processor and a memory connected to the processor. The memory may have a constrained capacity. The memory may contain an extensible set of rules for deriving additional semantic information from available information at the embedded device. The processor and the memory with the extensible set of rules may constitute a semantic rule engine. The semantic rule engine may apply the extensible set of rules to the available information to derive the additional semantic information.