Techniques are provided for generating and retrieving change summary data and aggregated model version data for an infrastructure model. A process obtains a briefcase representing a particular version of the infrastructure model and one or more changesets. The process applies the changeset(s) to the briefcase to construct a briefcase that represents a newer version of the infrastructure model. The process compares the briefcases to generate a change summary indicating modifications between the two versions. Further, the process generates aggregated model version data as the infrastructure model transitions to newer versions. The process updates the aggregated model version data utilizing the change summaries such that the aggregated model version data is comprehensive regarding each element that is and was included in the infrastructure model from its genesis to its current state. A client device issues requests to obtain a particular version of the infrastructure model and/or to obtain modifications between versions.