The establishment of linked data principles has ushered in a remarkable new era of widespread semantics-based interoperation. In particular, the use of RDF (Resource Description Framework), SPARQL and HTTP (HyperText Transfer Protocol) allows for a high degree of generic tool support and lightweight composition of data sources. This rosy picture, however, mainly applies to static data. When it comes to dynamics – both on-the-fly computation and the causation of side effects – the current norm is to drop the use of RDF in favor of JSON and XML (eXtensible Markup Language). By introducing updates, the core SPARQL standard starts to address dynamics, but only in a very limited manner.