Should have specified robosats does not do submarine swaps: they are custodial (at least that's how I remember it)
To be clear: got nothing against Boltz. But just to be aware of the possible alternatives you have for submarine swaps, without having to spin up your own. Bolts here posts a great resource.
You also have robosats which is federated: http://robosatsy56bwqn56qyadmcxkx767hnabg4mihxlmgyt6if5gnuxvzad.onion
Discussion
Escrow swaps