Project Introduction

Notional fixed rate lending agreement, using a new type of on-chain automatic market maker AMM for DeFi, CeFi and institutional traders to borrow at a fixed rate on the Ethereum network. Contributions include: the concept of fCash, periodic maturities, portfolios, and cash settlement.

fCash

fCash is a tokenized representation of the fCash flow. It represents the amount of tokens (i.e. Dai) that an account is entitled to receive (CASH_RECEIVER) or obligated to pay (CASH_PAYER) on its specified maturity date. For example, if an account holds +100 fCash tokens expiring at timestamp 100, it is entitled to 100Dai at any time greater than or equal to timestamp 100. Similarly, -100 fCash tokens for the same term means that the account is obliged to pay 100Dai at timestamp 100. The lending mechanism will be described in detail next.

A fCash with an expiry date (i.e. expiring at timestamp 100) is interchangeable with other fCash tokens with the same expiry date. However, it is not directly interchangeable with fCash of different maturities. Note also that the right to receive fCash (CASH_RECEIVER) is freely transferable, but the obligation to pay (CASH_PAYER) is not.

Finally, fCash tokens are not strictly ERC20 tokens, because fCash tokens of different maturities cannot be integrated with each other, fCash tokens can be represented under the ERC1155 token standard, which allows for interoperability .