Express Session Middleware

express-session is a robust and widely-used session middleware for Express.js applications, currently stable at version 1.19.0. It provides server-side session storage, managing session IDs via cookies while keeping the actual session data on the server, which is a key security differentiator compared to client-side cookie storage. While the core package offers a default `MemoryStore` for development and debugging, it explicitly warns against its use in production due to memory leak risks and lack of scalability, promoting a rich ecosystem of compatible external session stores. The project maintains a steady release cadence, with recent updates focusing on features like dynamic cookie options, improved security tooling, and dependency updates, ensuring ongoing compatibility and enhancements for Node.js environments (supporting Node.js >= 0.8.0). It has evolved to directly manage session cookies, making the `cookie-parser` middleware optional and recommending careful use if both are present to avoid secret mismatches.