Tutorials, stack comparisons, tool reviews, and productivity tips — code that ships.
A production incident walkthrough: Node.js connection pools silently fill with dead TCP sockets, every outbound request hangs forever, and your service looks down while the downstream API is healthy. Here are the four timeout values (connect, response, idle, and keepalive) with the working Agent and fetch config that prevents it.
A single slow report endpoint consumed every connection in the pool, and your login API started timing out. Here is how the bulkhead pattern isolates failure domains in Node.js: with semaphores, separate pools, and the fast-fail logic that keeps the rest of your service alive.
Stop drilling requestId and logger objects through twelve layers of function signatures. Here is how to use Node.js AsyncLocalStorage to attach context to the async chain itself, with working Express middleware, auto-enriched logging, and the three pitfalls that break context in production.
The batch job runs fine locally and explodes in production with ERROR: 40P01 deadlock detected. Here is how to make Postgres tell you exactly which queries fought, how to reproduce the race in a test script, and the three lock-ordering rules that eliminate deadlocks without guesswork.
Your API health checks pass, your downstream service is fast, but p99 latency still spikes under load. The culprit is often the Node.js HTTP connection pool. Here is how to measure it, size it, and stop throwing 500s at the problem.
Two API requests update the same row. One silently disappears. Here is the compare-and-swap pattern that fixes it without adding pessimistic lock contention to your database.
You added read replicas to scale reads. Then users started seeing 404s for records they just created. Here is the request-scoped routing pattern that fixes replication lag without giving up the performance win.
Offset pagination looks fine on page one and falls apart on page two hundred. Here is the exact SQL and Node.js code to replace it with cursor-based pagination that stays fast, avoids duplicate rows, and survives concurrent writes.
A user uploads a 40MB CSV and your API health checks start failing, not because the request is slow, but because JSON.parse blocked the event loop for two seconds. Here is the 60-line worker thread pool that moves CPU-bound work off the event loop, with the benchmark that proves the difference.
Your "just POST to the callback URL" webhooks are creating angry customers, retry storms, and silent data loss. Here is the architecture (queue, circuit breaker, dead-letter, and backoff) that turns fire-and-forget HTTP into a delivery system you can monitor and trust.