I. IntroductionDecentralized Finance (DeFi) has evolved through multiple generations:V2 introduced composability and AMM-based trading.V3 improved capital efficiency through concentrated liquidity.V4 brought modularity and programmability with Hooks.This comparison explores the key features, advantages, and limitations of each stage.II. DeFi V2: The Era of ComposabilityFeaturesAMMs like Uniswap V2 enabled permissionless token swaps.Composable “money legos”: lending, borrowing, trading integra...