# Introduction

IMPETUS Solver provides a framework for custom material models through dynamic-link library (DLL) or shared object files under Linux. Users can compile their own user-defined materials, which are then linked to the software at the start of a simulation. This approach offers several advantages, including seamless compatibility with any version of the software, provided there have been no major changes to the interface.

Users can take advantage of the latest software updates without requiring significant modifications to their custom material models. By incorporating specialized knowledge and expertise into their simulations, users can leverage proprietary material properties or complex constitutive relationships that may not be readily available in standard material models.

The ability to link up to eight user-defined material models also provides flexibility in modeling complex systems comprising diverse materials. This feature enables users to tailor the solver's behavior to meet specific simulation requirements, thereby increasing its overall utility and effectiveness.

## Licence

This IMPETUS User material package and documentation are released under the MIT License.

    MIT License

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