The talk is about using Cilium and Grafana for observability in free and open source software development. The speaker introduces Cilium, a company that maintains Cilium and EBPF, and explains that EBPF is to the kernel what JavaScript is to the browser, allowing for the creation of dynamic programs. Cilium runs on EBPF and provides networking, observability, and service mesh capabilities. The speaker discusses the challenges of observability at scale, such as the finger-pointing problem and the signal-to-noise problem. They explain that Cilium addresses these challenges by providing identity-aware observability and security, using labels to create unique identities and track service-to-service communication. The speaker also introduces Hubble, Cilium's observability solution, which retrieves data from Cilium agents and provides service dependency maps, flow visibility, and metrics. They discuss how Hubble integrates with Grafana to provide layer 7 metrics and tracing, allowing for the monitoring and troubleshooting of applications. The speaker also demonstrates a live demo of Cilium and Grafana in action, showcasing how metrics and traces can be monitored and analyzed. They conclude by providing resources for further information and answering audience questions.