The modeling and simulation of morphogenetic phenomena require to take into account the coupling between the processes that take place in a space and the modification of that space due to those processes, leading to a chicken-and-egg problem. To address this issue, we proposed to consider a growing structure as the byproduct of a multitude of interactions between its constitutive elements. An interaction-based model of computation relying on spatial relationships has then been developed leading to an original style of programming implemented in the MGS programming language. Contributions of MGS include a generic programming mechanism that captures most of the unconventional computing models by simply varying the underlying structure of interactions. I will introduce the interaction-based way of programming and review some current works taking roots in the fertile ground of MGS.