# Technical repositories The project stack is intentionally small and modular: a few core libraries, a focused set of lighthouse applications, and a handful of tools that unlock geometry handling, scalable discretization, and workflow orchestration.
Core libraries, lighthouse applications, and enabling tools behind dealii-X.
Libraries Core numerical building blocks deal.II, PSCToolkit, MUMPS Applications Digital twin demonstrators Brain, heart, lungs, liver, mechanobiology Tools Meshing and polytopal workflows Gmsh and Polydeal Interface Low-code orchestration Node-based workflow authoring and HPC scheduling
```{toctree} :hidden: :maxdepth: 2 libraries/index applications/index tools/index user_interface/index ```