Understanding the flow of requests in complex microservices architectures can be a daunting task. Distributed tracing emerges as a powerful solution, offering a clear, end-to-end view of how requests traverse various services. This article dives deep into implementing distributed tracing for FastAPI applications using OpenTelemetry, the vendor-neutral standard for instrumentation. We’ll cover setup, automatic and manual instrumentation, context propagation, and exporting traces to popular backends like Jaeger, empowering you to debug and optimize your microservices with unparalleled visibility.