With the development of the industry, privacy has become more and more important in web3, but the regulation of the industry by various governments is also becoming more and more strict, so we need to find a balance between privacy and compliance.
We recommend users to deposit into the Soda Lending Pool in priority. In this way, you can mix your private behaviors with normal behaviors in addition to earning interest on your deposit. We will support the deposit of three assets: SOL, USDC, USDT
In the process of depositing, the user will automatically use the viewing public key to generate an unique commitment through zero-knowledge proof. When the user withdraws, a nullifier corresponding to the commitment will be generated on the chain.
The commitment is a nullifier through the viewing public key. The encrypted results are both available on the chain, but only the user himself and the private smart contract holding the observer’s private key can find correspondence between 'commitment' and 'nullifier'.
We will generate the viewing key in a third-party privacy computing platform to ensure that it will not be abused, and community will vote first when it is called. The regulatory institution or security agency can apply for this key when problem fund are detected.

For more information: https://medium.com/@sodaprotocol/how-to-implement-compliance-regulations-in-coin-mixer-6604af2c0974