Ok probably Fedis will suit this use case more, depositing lager amounts and then withdrawing it but good point the non-custodial part is important for coin joining

The lightning bond scheme based on the htlc smart contract is very effective to preserve trust in the network. Is there a mechanism by which a digital contract could be used to back cashu tokens with a posted "honesty bond" by the mint? Then any token holder can provide their token as "proof of promise to pay" and if the mint fails proof of reserves, the bond can be used to pay the token onchain or over lightning? Maybe even the bond could be in the form of ecash stored at a "more trusted" mint?