Super-cracked Brazilian Bitcoin devs from @nprofile1q... implemented a Proof of Liabilities scheme for @Cashu Ecash mints.

All the bells and whistles included: Merkle sum trees, OpenTimeStamp anchoring, a spec, and a working implementation.

Gist: https://gist.github.com/victorandre957/4f497d385e1fd9a47898480903f56b3e
Spec: https://github.com/victorandre957/nuts/pull/1
Nutshell implementation: https://github.com/victorandre957/nutshell/pull/1
Original idea: https://gist.github.com/callebtc/ed5228d1d8cbaade0104db5d1cf63939