multim

multiM is an open-source framework for multi-model simulation and co-simulation that enables the integration of heterogeneous models across domains. It focuses on time-coordinated execution, interoperable data exchange, and comparative scenario analysis. The goal is to allow researchers and practitioners to assemble complex, cross-domain models without rewriting existing code.

The project supports coupling models with different time steps, data formats, and software environments through a mediator that handles synchronization, data translation, and error handling. It also provides facilities for uncertainty quantification and sensitivity analysis across coupled components.

Architecture and components: a lightweight core engine that coordinates execution, a library of adapters for common modeling tools, and a plugin system for solvers, analysis tools, and visualization. The framework exposes APIs in Python and C++, and uses a model interface description to declare participating models and their inputs, outputs, and synchronization points.

History and governance: multiM originated from a collaboration among universities and industry partners in the mid-2010s and has evolved through several major releases. It is maintained by a community-driven foundation that promotes open contribution, documentation, and interoperability standards.

Applications: the framework has been used in environmental and climate modeling, energy systems planning, urban and transportation simulations, and supply-chain analysis. It supports coupling legacy models with modern data pipelines and enables scenario comparison and optimization workflows.

Reception and status: multiM has seen broad adoption in academia and growing interest from industry users. Documentation, tutorials, and example projects accompany releases. It is distributed under an open-source license, with ongoing development and community forums for support.