Software as Scientific Infrastructure: CIG’s Role in Computational Geodynamics and Lessons from Developing ASPECT

Modeling software is integral to computational geodynamics, enabling quantitative investigation of planetary mantle, lithosphere and core dynamics across a wide range of spatial and temporal scales. Over the past two decades, the field’s software ecosystem has shifted significantly: codes that were once developed and maintained within single research groups have increasingly evolved into large, modular packages sustained by multi-institutional and often international collaborations. One important factor in this transition has been the establishment of community organizations like the Computational Infrastructure for Geodynamics (CIG), which has provided coordination and shared capacity that individual groups typically cannot sustain on their own.
In this contribution, I highlight benefits and lessons learned from work within CIG and from the development of the geodynamic modeling software ASPECT (Advanced Solver for Planetary Evolution, Convection, and Tectonics). Community organizations can accelerate scientific software development in several ways. Shared infrastructure (project landing pages, established user forums) improves discoverability and supports software adoption by the community. Targeted support, including seed funding, helps projects invest in feature development and maintenance. By streamlining software release and distribution and promoting robust development and testing workflows, community organizations improve software quality and reliability. Training the next generation of computational geoscientists through workshops, tutorials, and user support, builds shared expertise and makes community software more sustainable. Collectively, these activities reduce duplicated effort, lower barriers to entry for new users and contributors, and create pathways for software to evolve in step with scientific and numerical-method advances.
ASPECT provides a concrete example of this community-driven model. Designed to simulate thermal convection with a primary emphasis on Earth’s mantle, it has now been used for a broad range of applications including crustal deformation, magma dynamics, and fluid flow, convection on icy satellites, deformation of the inner core, and digital twins of mineral physics experiments. This widening scope has been possible because ASPECT prioritizes usability and extensibility, to accommodate evolving model complexity, and leverages modern numerical methods such as adaptive mesh refinement and robust linear/nonlinear solvers. From the start, ASPECT has been designed for large-scale parallel simulations required for problems with small-scale features embedded in mantle-scale domains.  It also strategically builds on established external libraries (e.g., deal.II, Trilinos, p4est) rather than re-implementing core algorithms. ASPECT’s success has been enabled by a well-tested framework, extensive documentation, a plugin architecture that simplifies customization, and active encouragement of community contributions through support and recognition. Together, these elements illustrate how organizational infrastructure and software design choices support long-term development and continued methodological innovation in geodynamic modeling, enabling robust simulations that address increasingly complex scientific questions.