USDs is a stablecoin which generates auto-yield natively. Currently, USDs is live on Arbitrum, the largest Layer-2 Ecosystem of Ethereum. The highlights of this protocol:

• Auto-yield - Users holding USDs in their wallets automatically earn organic yield. No staking is required by the end user. Users do not need to spend gas calling the smart contract to claim their yield. 
• Layer-2 native — Cheaper transaction fees on Arbitrum make this protocol retail investor-friendly
• Fully Backed Model - USDs is 100% backed by a diversified basket of whitelisted crypto assets (stablecoins).

To mint new USDs, minters only need eligible collateral. No fee required for minting USDs. Currently the protocol is accepting USDC, DAI, FRAX and VST as collateral and more tokens might be added to this list in future. However, USDs tokens are fungible and redeemable in the same way, independent of their underlying minting collateral. It acts as an IOU on the pooled collateral. The protocol will mint 1 USDs by collecting 1 USD worth of collateral.