In the field of the 3D reconstruction of cities in the past there is a raising interest in the creation of models that are not just geometrical, but also informative, semantic and georeferenced. Despite the advancements that were done in the historical reconstruction of architecture and archaeology, the solutions designed for larger scale models are still very limited. On the other hand, research on the digitisation of current-day cities provides useful instruments. In particular, CityJSON - a JSON encoding of CityGML - represents an easy-to-use and lightweight solution for storing 3D models of cities that are geolocated, semantic and that contain additional information in the form of attributes. This contribution proposes (1) to extend the schema to the needs of a historical representation; and (2) to incorporate the newly created model in a continuous flow pipeline, in which the geometry is dynamically updated each time an attribute is changed, as a means to foster collaboration.