Abstract
Over the past decade executable biology has proven itself as a useful tool for supporting understanding of biological processes. Executable biology covers very distinct approaches to modelling that treat biology at different levels of granularity. In this talk, we will touch upon our work that sees cells as state machines and combines machines for different cells to create a larger model that allows to study cell-cell interaction and communication as well as intra-cellular processes. This level of modelling imposes certain restrictions on the way cell programs are updated in a simulation and on the types of analysis that can be applied to them. I will survey some of our approaches for putting cells together and how these affect our ability to analyze these models.