Ethereum JSON-RPC Middleware for json-rpc-engine

eth-json-rpc-middleware provides a collection of Ethereum-specific middleware functions designed to integrate with `@metamask/json-rpc-engine`. It facilitates common RPC patterns like block tracking, transaction handling, and EIP-standard implementations (e.g., EIP-5792, EIP-7715). Maintained by MetaMask, this library is actively developed, evidenced by its frequent major releases and updates to support the latest Ethereum specifications. The current stable version is v20.0.0, which notably introduced separate CommonJS and ESM distributions. Its key differentiators include tight integration within the MetaMask ecosystem and robust support for advanced wallet and RPC interactions, making it a foundational component for building dApps and Ethereum tooling.