SimpleCommands.cs

public interface ICommandHandler<TCommand> {
  void Handle(TCommand command);
}

public interface IDispatcher {
  void Invoke<TCommand>(TCommand command);
}

public class Dispatcher : IDispatcher {
  public void Invoke<TCommand>(TCommand command) {
    var handler = ObjectFactory.GetInstance<ICommandHandler<TCommand>>();
    handler.Handle(cmd);
  }
}

public class GetUsersCommand {
  public IList<User> Result { get; set; }
}

public class GetUsersHandler : ICommandHandler<GetUsersCommand> {
  private ISession session;

  public GetUsersHandler(ISession session) {
     this.session=session;
   }
   
  public void Handle(GetUsersCommand cmd) {
      var users = session.List<User>();
      cmd.Result = users;
  }
}