Maker (MKR) had recently approved stablecoins TUSD (TrueUSD) and USDC-B (a USDC token variant with different risk parameters) as new collateral assets in the Maker Protocol. Users could use both tokens to open Maker Vaults to generate Dai. However, soon after, Maker made TUSD temporarily unavailable.
TUSD and USDC-B (USDC with different risk parameters) have been added to the Maker Protocol.
Both can now be used to generate #Dai.
— Maker (@MakerDAO) June 4, 2020
The new tokens act as an emergency credit facility during times when keeper liquidity is overwhelmed (such as busy liquidation periods with large amounts of collateral being auctioned). The USDC-B collateral type will remain unused unless there is a severe and acute liquidity issue in the Dai markets. Users can connect their wallets to Oasis Borrow and lock the tokens in a Maker Vault to generate Dai.
However, Maker had to take a step back. TUSD underwent 3 contract upgrades. This triggered Maker’s safety measures that no unaudited external code can interact with the Maker Protocol. Maker plans to bring back TUSD after code is upgraded and audited.
TUSD vaults are temporarily unavailable due to a TUSD's unannounced contract upgrade, triggering safety measures that no unaudited external code can interact with the Maker Protocol. Will update after code is upgraded and audited.
— Maker (@MakerDAO) June 5, 2020
Both TUSD and USDC-B are US Dollar-backed ERC20 stablecoins. Questions have been raised on Dai getting more centralized. Maker maintains its stance that DAI remains decentralized and permissionless. However, it is to be noted that, DAI is ultimately backed by MKR. If collateral fails then MKR will be printed to cover the shortfall. Centralized currencies have more risk of failures. This causes bad debt and leads to MKR being printed (depending on the level of surplus DAI held by the protocol). The less MKR printing, the better.
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