i just gave a look at it again, i still cant understand how exactly Ark stops the service from emptying the pool.

i mean in my head i tried to imagine how i would make something like Ark. like how would i be able to receive UTXOs on base layer for my VTXOs, without service being online, and how would the service stop liars.

but i have no idea what is stopping the service from creating fake VTXOs to empty the pool. i can imagine users might try to prove service is lying onchain, but then they have to share some history onchain? which makes it expensive. idk how it works. exactly. but doesnt sound right.

i mean i like cashu. and mints in cashu can also take the bitcoin and leave, but that protocol doesnt claim to be non-custodial. also in cashu you can input ecash from multiple mints to pay a single lightning invoice which is cool.

but cashu mints are kinda want too much fee for lightning payments.

thats the only downside. many lightning wallet even if they are custodial, want way too much fee i think. idk.