Buglyst Blog
Learn to debug under pressure.
Playbooks for fast pattern recognition, guides for the full investigation, and articles for the engineering judgment around the edges.
17 playbooks · 509 guides · 95 articles · 12 linked practice labs ·skip to practice
Fast pattern recognition for the production failures engineers see most often.
17 playbooks
Debugging Env Var Issues
A concise checklist for incidents where local works but CI, staging, or production changes behavior.
Debugging Cache Stampedes
How to recognize and contain request spikes when cached data expires.
Debugging CORS Origin Bugs
A practical way to inspect origin parsing, credentials, and header behavior.
Debugging Retry Bugs
Retry issues often hide the first failure and create duplicate work.
Debugging Timezone Bugs
Time bugs usually live at day boundaries, DST changes, and unit conversions.
Debugging Pagination Bugs
Pagination bugs hide in boundary math, cursor reuse, and new records arriving between pages.
Structured investigations for the failure modes engineers meet in real systems.
Kubernetes pod CrashLoopBackOff: how to debug crashing pods
Your pod starts, crashes, restarts, crashes again. The CrashLoopBackOff status means Kubernetes is giving up. The pod logs hold the answer.
SSL certificate error after deployment: how to debug TLS issues
Your site was working with HTTPS. After a deployment, browsers show SSL errors. The certificate expired, was not renewed, or the domain changed.
Frontend build works locally but fails on Vercel or Render: how to debug it
Your build command succeeds locally but fails when Vercel or Render runs it. The platform has a different Node version, memory limit, or build settings.
API timeout: how to debug request timeout issues
Your API endpoint returns a timeout error. The request takes longer than the configured timeout, but the operation might have succeeded silently on the server.
Duplicate emails sent by retry bug: how to debug it
Your email service retries a failed send, but the first send actually succeeded. Users get two, three, or ten copies of the same email.
Pagination off by one bug: how to debug pagination errors
Your paginated list skips the first item, shows the last item twice, or has an empty last page. The offset, limit, or page calculation is off by one.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Debugging Webhook Delivery Failures: What the Logs Don't Tell You
HTTP 200 doesn't mean your webhook was processed. A practical guide to the network and middleware layers that silently drop webhooks.
Debugging HTTP Headers with curl: From Basic Flags to Packet-Level Inspection
A practical guide to inspecting HTTP request and response headers with curl, covering basic flags, debugging tricky issues, and understanding what your headers are really doing.
Debugging WebSocket Real-Time Features: Packet Loss, Reconnect Storms, and Silent Failures
WebSocket debugging goes beyond console.log. I cover packet capture with tcpdump, reconnect backoff strategies, and a war story about a silent failure that took down a production chat feature.
Rest API Design Mistakes That Inject Bugs Into Your System
Most API bugs aren't in the implementation—they're baked into the contract. Here are the design errors I've seen cause the most production incidents.
Blameless Postmortems: How We Fixed Root Causes Without Firing Anyone
A practical guide to running postmortems that focus on systemic failures, not individual mistakes. Includes a real incident breakdown from a production database outage.
Chaos Engineering at 3 AM: When Our Kubernetes Cluster Lost Its DNS
We ran a chaos experiment on our Kubernetes cluster and found a subtle DNS misconfiguration that would have caused a cascading failure. Here's how we did it and what we learned.