The V4 upgrade introduces a "singleton" liquidity architecture that consolidates liquidity into a single smart contract, reducing gas fees, lowering swapping costs, and enabling native ETH transactions

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The protocol also builds upon the capital efficiency gains of Uniswap V3 by introducing several architectural improvements and features. One of the most notable changes is the implementation of a "singleton" liquidity architecture, which consolidates liquidity through a single smart contract. This change aims to provide faster transactions, lower gas fees, and an improved user experience.