Sky's decentralization review

@makerdao' Sky is a stablecoin protocol allowing users to mint its USDS stablecoin through Collateralized Debt Positions with a variety of crypto collateral assets. Sky is built on the Maker protocol, by the MakerDAO, to replace the DAI stablecoin and allow for the 1:1 conversion between DAI and USDS. 

USDS can further be staked for the yield-bearing sUSDS token. Various levels of control over the Sky protocol are exercised through an onchain governance system.

Sky Community - Sky.money is a non-custodial gateway to the decentralised Sky Protocol. It is accessible to eligible users 24/7.

DeFiScan assesses and monitors the maturity and risks of DeFi protocols fostering Transparency and Security.
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⛅Autonomy
🔴High Autonomy Centralization Score
Circle's $USDC
Sky has a centralized dependency on Circle and its $USDC stablecoin token. Users can mint $USDS from $USDC at a fixed 1:1 rate. This means that $USDS is directly pegged to $USDC which is a centralized stablecoin.

This conversion may be stopped or paused in an emergency Sky Governance proposal. There is a debt ceiling limiting how much $USDS can be backed by $USDC. Nonetheless, at the time of writing, this debt ceiling is high enough that it does not prevent more than 50% of the collateral in Sky from being backed by USDC. The ceiling is explained further in the dependencies section.

🚨Upgradability
🔴High Upgradability Centralization Score
$USDS and $sUSDS, respectively Sky's stablecoin and its corresponding yield-bearing version, are upgradeable contracts through Sky Governance proposals. Updating those contracts could change the entire logic of those tokens and may incur a loss of funds for users.

Critical parameters in the Sky protocol can be changed through Sky Governance proposals. Unwanted updates to these parameters can result in the loss of funds, loss of unclaimed yield, or otherwise materially impact the expected protocol performance. 
Example actions are: 
- Forced liquidations, which would result in loss of user funds.
- Creating unbacked debt, which could endanger the protocol's stability.
- Pausing the contracts, which could trap user funds for an undetermined amount of time.

Decentralization Assessments
⛓️Chain
🟢The report is concerned with the Sky instance deployed on Ethereum mainnet. Ethereum achieves a Low chain centralization score.