slackbuilds_ponce/development/dotnet-runtime-3.1

.NET Core is an open-source, general-purpose development platform
maintained by Microsoft and the .NET community on GitHub.  It's
cross-platform (supporting Windows, macOS, and Linux) and can be used to
build device, cloud, and IoT applications.

This package contains everything you need to run a .NET application.
If you want to build apps, install .NET Core SDK (dotnet-sdk), which
contains this runtime too.