stCELO vs rstCELO
stCELO is an ERC-20 compatible non-rebasing token, which is intended to further encourage active participation of users in the protocol, dApps, and wider Celo ecosystem. Non-rebasing means that the amount of tokens a user has in their wallet stays constant over time if that user takes no actions. Consequently, one stCELO is increasing in value over time (measured in CELO), as epoch rewards are being accrued in the protocol*. This may be helpful for DeFi protocols, for example bridging protocols, that do not natively support rebasing tokens.
However, to provide maximal flexibility for developers, StakedCelo also provides a rebasing token, called rstCELO, which wraps around stCELO. The core feature of rstCELO is that it is backed by exactly one CELO, so when withdrawing rstCELO from the StakedCelo protocol one CELO should be received for each rstCELO. This can be a useful property for certain third-party protocols that want to integrate StakedCelo, for example for a decentralized exchange that is optimized for 1:1 exchange rates. rstCELO is simply a wrapped form of stCELO and the two tokens can therefore be redeemed for one another atomically and instantly via a smart contract call at any time.