rayeaster/fair-selling

Work towards a trust-minimized (one day trustless) token swapper. Currently: OnChainPricing & Cowswap Contract Swapper. One day: Automatic Limit Order Swap Protocol

Fair Selling

Release V0.2 - Pricer - BribesProcessor - CowswapSeller

CoswapSeller

OnChain Integration with Cowswap, all the functions you want to:

• Verify an Order
• Retrieve the OrderUid from the orderData
• Validate an order through basic security checks (price is correct, sends to correct recipient)
• Integrated with an onChain Pricer (see below), to offer stronger execution guarantees

BribesProcessor

Anti-rug technlogy, allows a Multi-sig to rapidly process cowswap orders, without allowing the Multi to rug Allows tokens to be rescued without the need for governance via the ragequit function

MainnetPricing

Given a tokenIn, tokenOut and AmountIn, returns a Quote from the most popular dexes

Dexes Support

• Curve
• UniV2
• UniV3
• Balancer
• Sushi

Covering >80% TVL on Mainnet.

Example Usage

NOTE: Because of Balancer and UniV3 (go bug their devs pls), the following functions are not view, you must .call them from offchain to avoid spending gas

isPairSupported

Returns true if the pricer will return a non-zero quote NOTE: This is not proof of optimality

    /// @dev Given tokenIn, out and amountIn, returns true if a quote will be non-zero
    /// @notice Doesn't guarantee optimality, just non-zero
    function isPairSupported(address tokenIn, address tokenOut, uint256 amountIn) external returns (bool)

In Brownie

quote = pricer.isPairSupported.call(t_in, t_out, amt_in) ## Add .call to avoid paying for the tx

findOptimalSwap

Returns the best quote given the various Dexes, used Heuristics to save gas (V0.3 will focus on this) NOTE: While the function says optimal, this is not optimal, just best of the bunch, optimality may never be achieved fully on-chain

    function findOptimalSwap(address tokenIn, address tokenOut, uint256 amountIn) external virtual returns (Quote memory)

In Brownie

quote = pricer.findOptimalSwap.call(t_in, t_out, amt_in) ## Add .call to avoid paying for the tx

Mainnet Pricing Lenient

Variation of Pricer with a slippage tollerance