StaFi is a DeFi protocol that unlocks the liquidity of collateralized assets. Users can mortgage PoS tokens (such as DOT, FIS, etc.) through the StaFi staking contract, and get rTokens (such as rDOT, rFIS, etc.) in return. These tokens can be used for transactions to hedge against market fluctuations, while still earning staking income.

FIS is the native functional token of the StaFi protocol, which is used for the following functions:
Mortgage: Validators in the StaFi consensus need to stake FIS to join the consensus network, and nominators need to mortgage FIS to participate.
Transaction fees: In order to avoid system abuse, the initiator of the transaction must pay FIS to access computing resources. In this way, invalid transactions will be eliminated, similar to the functionality of other Polkadot chains.
On-chain governance: FIS holders can participate in changing StaFi protocol parameters, vote for protocol upgrades and determine the development process. Anyone can make a proposal to the agreement, but only FIS holders can vote for or against the proposal, that is, 1 FIS account represents 1 vote.
Value Capture: Most of the StaFi Protocol's platform fees (transaction fees and liquidity fees) will be used to fund the buyback and burning of FIS tokens. Depending on governance decisions, the distribution of StaFi revenue may change.

StaFi releases the liquidity of mortgage assets through mortgage contracts. The protocol consists of the following main components:
rToken: rToken is a derivative asset issued by StaFi based on mortgage tokens. Holding rTokens means that you can apply for redemption of native mortgage tokens at any time. This also means that rToken holders are entitled to the benefits of staking tokens.
Mortgage contract: A set of codes containing StaFi's core functions, such as staking, redemption, and transactions. It also records the mapping relationship between rToken and the underlying mortgage token. The role of the collateral contract in StaFi is similar to that of the CDP contract in MakerDAO.
Multi-signature account: StaFi is used to manage staking tokens and temporary accounts participating in staking.
StaFi Special Validator (SSV): The difference between SSV and SV is that SSV is responsible for managing multi-signature accounts and verifying the original chain transaction status. They use multi-signature transactions to process staked tokens in their accounts.