Patchwork is an Ethereum protocol and accompanying toolset that provides a fully onchain data layer for onchain entities. It organizes data as composable NFTs via the Patchwork721 standard (an extended ERC721): contracts define data schemas (like database tables), and each token represents a data record. It supports three extension types: Patch (data permanently affixed to a target entity), Fragment (transferable standalone data blocks), and Assignee (a container that holds Fragments). Developers can use the PDK low-code tool to generate Solidity contracts from JSON, or directly integrate the interfaces. Data is interactable by smart contracts, queryable, and supports permission management and event indexing.