Multiscale universal interface v2.0: Lowering barriers to scalable multiphysics coupling
Description
We present the Multiscale Universal Interface 2.0 library, the next major release of the lightweight, header-only C++ library for scalable multiphysics or multiscale code coupling. Designed to lower barriers to integration, this release introduces key enhancements in non-conformal data mapping, coupling algorithms, performance scalability, and language interoperability. A new Radial Basis Function spatial sampler enables conservative data transfer across non-conformal interfaces, while built-in modules support robust relaxation schemes for strongly coupled systems with dynamic interfaces. The addition of a dedicated linear algebra subsystem eliminates previous external dependencies and provides a foundation for advanced interpolation and solver acceleration. Accessibility is further expanded through redesigned wrappers for C, Fortran, and Python, and smart communication strategy improves High-Performance Computing scalability via refined communication strategies. Benchmarks on supercomputers demonstrate near-linear scalability under heavy communication loads. This release represents a significant step toward enabling flexible, high-performance multiphysics simulations across diverse platforms and disciplines.