04 / Field notes

Practical thinking for building and running software.

Concise guides on engineering decisions, deployment and the details that matter once software reaches production.

Browse topicsDeploymentInfrastructureReliabilityBackendData

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Observability that answers useful questions

A focused approach to logs, metrics, traces and alerts that helps teams understand production instead of collecting noise.

05 entries

A practical expand-and-contract workflow for changing production schemas while old and new application versions coexist.

How idempotency keys, request state and response replay prevent duplicate payments, orders and background jobs.

A repeatable incident workflow for narrowing the problem, protecting evidence and restoring service safely.

How DNS, TLS and Nginx fit together—and the configuration details that prevent redirect loops and exposed origins.

A production-focused checklist for smaller images, safer containers, reliable health checks and predictable releases.