One of my current talks focuses on Observability in general and Distributed Tracing in particular, with an OpenTelemetry implementation. In the demo, I show how you can see the traces of a simple distributed system consisting of: the Apache APISIX API Gateway, a Kotlin app with Spring Boot, a Python app with Flask, and a Rust app with Axum. Earlier this year, I spoke and attended the Observability room at FOSDEM. One of the talks demoed the Grafana stack: Mimir for metrics, Tempo for traces, and