Decentralised Privacy leveraging @Nillion Networks

[jason-homeboy]

Introduction
Kagami is a new decentralised custodian allowing for open (anyone can use it) and low cost custody whilst still offering the sophistication found in expensive centralised custodians. Deep dive here https://docs.kagami.pro

Nillion Networks allows decentralised compute in a privacy preserving manner. Its decentralisation, integration with Ethereum and ability to scale make it more attractive than private compute environments.

What are we building and why ?
Custodians offer a policy layer. This handles tasks such as whitelists or transaction limits. For our pilot project with Nillion (which is proof of concept stage) Kagami is building a decentralised transaction limit for ethereum wallets. What this means is that the wallet owner can set a transaction limit that is private from even the custodian (in this case us) and everyone else whilst also being fully decentralised.

Some of the things we have learned
We have learned that there is great interest in this pilot. Centralisation of policies does not sit well with many people who compromise in order to get risk controls on their wallets but wish for a better way.

We have learnt that with decentralisation comes challenges because the updating and modification of policy logic and limits is more complex than using centralised database/code system. However the privacy and decentralisation benefits are of course the end goal so we accept this.

Tips for devs

1. Read the Nillion docs and examples they are informative. Don't skip bits just read them!
2. Reach out to the Nillion team they are always helpful.
3. Nillion Network SDK may operate slightly differently to what you may have experienced but do not give up. As you learn the system it becomes apparent the advantages and opportunities it provides.

Demo

Please note this demo is specifically to test private policies only. It is not the Kagami decentralised custody offering itself which is yet to go live.

This video demo has been developed against the nillion-devnet see https://docs.nillion.com/nillion-devnet. It supports Sepolia ETH stored in pre-defined wallets named Operations, Sales, Payroll, Treasury. These represent the wallets of an organisation.

It consists of 3 programs:

1. Administrator program to see the spend limit for each wallet which is stored on nillion-devnet. This is run by the owner of the organisation. Importantly front end program has no visibility of what these limit values are yet can query if a transaction > limit.
2. Uplink program that makes requests to nillion-devnet on behalf of the front-end.
3. Front-end that allows anyone in the organisation (who has been allowed access of course!) to send ETH from the organisation wallets.

Videos:

Administrator program (Please watch FULLSCREEN if hard to see): https://drive.google.com/file/d/1hmaC-iKNVTM5wtI7UxB5hh2Kbx1pjJW_/view?usp=drive_link

Front-end program: https://drive.google.com/file/d/1Dz0WVBI94kVZGQ_s1S_Lf51wsCIH8JG0/view