How would you design observability for a production Node.js system using logging, metrics, tracing, and alerting?

Node.js is a JavaScript runtime built on Chrome's V8 engine. It uses a single-threaded event loop for non-blocking I/O.

While the JavaScript execution is single-threaded, Node uses libuv to handle system tasks in the background using a thread pool. This allows Node to handle thousands of concurrent connections without the overhead of thread context switching.