Once you build Swarm-NG library, you can use the command-line interface by invoking the executable bin/swarm.

To learn about all commands and switches refer to Swarm command-line interface

Alternatively, you can access Swarm-NG functionality via C++. For examples of how to use the Swarm-NG library, see Beginner tutorial for using the API, Advanced tutorial for using GPU integrators, and src/tutorials/*.cpp