Envoy
Envoy is a high-performance, open-source edge and service proxy designed for cloud-native applications. It provides critical networking functions like load balancing, observability, and security (e.g., TLS termination) for microservices architectures. Originally developed at Lyft, it is now a graduated project of the Cloud Native Computing Foundation (CNCF).
Developers should learn Envoy when building or operating distributed systems, especially in Kubernetes or service mesh environments, as it handles complex traffic routing, resilience patterns (like circuit breaking), and telemetry collection efficiently. It is essential for implementing service meshes like Istio, which rely on Envoy as the data plane to manage inter-service communication securely and reliably.