Pork Swap

PorkSwap is an on-chain system of smart contracts on the Binance Smart Chain, implementing an automated liquidity protocol based on a “constant product formula”. Each PorkSwap pair stores pooled reserves of two assets, and provides liquidity for those two assets, maintaining the invariant that the product of the reserves cannot decrease. Traders pay a 20-basis-point fee on trades, from which 15-basis-point fees goes to liquidity providers and 5-basis-point fee is used to buy back and burn PSWAP tokens. The contracts are non-upgradeable.

The PorkSwap protocol enables the creation of arbitrary BEP-20/BEP-20 pairs, rather than supporting only pairs between BEP-20 and BNB. It also provides a hardened price oracle that accumulates the relative price of the two assets at the beginning of each block. This allows other contracts on Binance Smart Chain to estimate the time-weighted average price for the two assets over arbitrary intervals. Finally, it enables “flash swaps” where users can receive assets freely and use them elsewhere on the chain, only paying for (or returning) those assets at the end of the transaction.

While the contract is not generally upgradeable, there is a private key that has the ability to update a variable on the factory contract to change trading fee on trades. This fee will initially be 20-basis-points, but could be changed in the future, in-case of changes due to governance.