Using extensions to group up systems

SystemSetup.cs

public Systems CreateSystems(Pool pool)
{
    return SceneSetup.CreateSystem()
      .Add(pool.CreateSystem<MoveAndRotateCameraSystem>())
      // Adding all animation systems
      .AddAnimationSystems(pool)
      .Add(pool.CreateSystem<UpdateActingSystem>())
      //...
      .Add(pool.CreateSystem<DestroySystem>());
}

public static class PoolAnimationSystemsExtensions
{
    public static Systems AddAnimationSystems(this Systems systems, Pool pool)
    {
        return systems
            .Add(pool.CreateSystem<RotationAnimationSystem>())
            .Add(pool.CreateSystem<MoveAnimationSystem>())
            //...
            .Add(pool.CreateSystem<ExitGateAnimationSystem>())
            .Add(pool.CreateSystem<CurseAnimationSystem>());
    }
}