Observability
7 engineering logs on Observability. Newest first.
- The replica lag you do not measure is the one serving checkout
Why byte lag reads zero on a broken replica, how read-your-writes breaks the moment you add a read replica, and why routing all reads to replicas is a correctness decision rather than a scaling one.
- Your ORM issued 400 queries and the p99 looked fine until it didn't
Why N+1 queries are invisible to every database side metric you own, how a getter call becomes a network round trip, and why the fix that looks obvious produces a cartesian product.
- Instrumenting AI Agents: Why the Apology Metric Is a First Class Reliability Signal
Track apology phrases as a first class SLO for AI agents: spikes reveal context starvation, timeout dropouts, and payload truncation across data boundaries.
- RSS vs VSZ in Virtual Memory: What the OOM Killer Actually Counts
malloc() grows VSZ, page faults commit RSS, and the Linux OOM killer only counts RSS. How virtual memory and lazy allocation decide which process dies.
- Designing Resilient APIs: Failure-Handling Patterns for Distributed Systems
Practical resilience patterns for distributed APIs: fail-fast, retries with backoff, circuit breakers, bulkheads, fallbacks, rate limiting, failover, and observability.
- Zero Trust Architecture: From Perimeter Walls to "Never Trust, Always Verify"
How Zero Trust Architecture replaces perimeter-based security: core principles, differences from traditional models and ZTNA, enabling technologies, and real-world implementations.
- System Migration: Minimize Downtime, Maximize Efficiency
A practical blueprint for system migration: isolated env, sync/async flows, bridge layer, traffic leakage, backup sync, and monitoring.