Modular Monolith Observability: Logging & Profiling
Answer-first: Observability in modular monoliths leverages in-process OpenTelemetry span propagation across module boundaries without network serialization overhead. Combining in-memory context tracking with structured logging reduces telemetry ingestion costs while retaining microservice-level latency visibility. Prerequisite: Before reading this part, please review Part 4: CI/CD Simplified. Part 5: Observability in Memory – When Everything Shares a Single Call Stack What You’ll Learn: In-Memory Trace Propagation: How Go context propagation handles tracing across package lines without network calls (~15ns vs 1.2µs). Cardinality Reduction: Techniques to strip connection attributes from logs, saving thousands in observability SaaS bills. Sampling & eBPF Profiling: How Pyroscope/Parca eBPF engines continuously profile Go runtimes under 1% overhead compared to heavy APM agents. When operating a production system, observability determines whether an engineer resolves an outage within minutes or spends hours troubleshooting distributed failure modes. Microservices architectures make telemetry expensive and complex through distributed network span propagation. ...