Timeswap is a decentralized lending protocol on Ethereum that uses an oracle-free AMM mechanism. It allows users to permissionlessly create fixed-term lending markets for any ERC-20 token pair. Users can take on three roles: lenders deposit assets to earn fixed interest, borrowers collateralize assets to borrow tokens and pay interest, and liquidity providers supply both assets and interest to earn transaction fees. Its core mechanism is the Duration-Weighted Constant Sum Product Market Maker (DW-CSPMM), which automatically discovers interest rates through constant sum and constant product formulas, and uses collateral ratios to ensure loan safety. All operations are executed via smart contracts, and assets are self-custodied by users.