AIP - 44: Add support for cbETH on Angle Borrowing Module on mainnet

This is a vote to accept cbETH as a collateral for agEUR on mainnet.

Context

Coinbase Wrapped Staked ETH (“cbETH”) is a a utility token that represents Ethereum 2 (ETH2), which is ETH staked through Coinbase. It accumulates staking rewards made by Coinbase when staking ETH.

It functions essentially like stETH (except that it's yield-bearing and not rebasing) in the sense that it is a liquid staking token that allows holders to get the benefits of staking without lockups or unbonding periods.

Yield for holding cbETH has consistently been over 4% over the past months, and circulating supply is around $1bn. The token is liquid on-chain, and it has a Chainlink oracle.

Proposal

The proposal is to add cbETH as a collateral for agEUR on mainnet, with the parameters proposed in this pull request and with the oracle implementation suggested here.

Implementation

Launching a new collateral asset is straightforward and only asks to deploy an oracle and a proxy on top of the base vaultManager implementation. It does not imply any extra maintenance.

Value to the protocol

Adding cbETH as a collateral for the protocol is a way for the protocol to remain at the edge when it comes to providing opportunities to ETH liquid staking derivatives. Angle is the cheapest place where to borrow against wstETH, there is a momentum to be built by doing this for every LSD which is already big enough. Angle would essentially be the cheapest place where to leverage

Risks

The main risk is to accumulate bad debt from cbETH liquidations (happening after an ETH price decrease or a cbETH depeg with respect to the normal track it should have with ETH). Those risks can be already addressed by the debt ceiling we propose to place on cbETH, and on the collateral factor + liquidation discounts that guarantee that even if the liquidation of a position fails to happen rapidly enough, then protocol still does not lose money if the position is liquidated at its max discount.

Voting Options

1. For, add cbETH
2. Against, do nothing