Modern Promise-Based Middleware

middleware-io is a lightweight, zero-dependency library for composing promise-based middleware in JavaScript and TypeScript applications. It provides a `compose` function similar to `koa-compose` and a `Composer` class for building middleware chains with various utility 'snippets' like lazy loading, forking, and concurrency control. The library is written in TypeScript, ensuring type safety and a robust development experience. Currently at version 2.8.1, its release cadence has been irregular since its active development phase around 2019-2021, with the latest significant changes related to `exports` in `package.json` for modern module resolution. Key differentiators include its self-sufficiency (zero dependencies), native ESM support, and a rich set of built-in middleware snippets.