node-newrelic is a production-grade APM agent library for Node.js, loaded into a host application via require('newrelic') or --require. It instruments Node's built-in modules and a broad ecosystem of third-party libraries—Express, Fastify, MongoDB, Redis, MySQL, AWS SDK, OpenAI, LangChain, gRPC, Kafka, and many more—to create transactions, segments, spans, metrics, errors, logs, and LLM events. These are aggregated in memory, sampled via priority queues, and harvested to the New Relic collector over HTTPS/gRPC, including infinite-tracing streaming. The agent also implements W3C tracecontext and New Relic distributed-tracing headers, supports serverless environments (AWS Lambda, Azure Functions), and includes an OpenTelemetry bridge for traces, metrics, and logs.