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.
18 playbooks · 509 guides · 96 articles · 13 linked practice labs ·skip to practice
Fast pattern recognition for the production failures engineers see most often.
18 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.
Pulumi State Drift: How Refresh Lies and What to Actually Do
A hard-nosed guide to diagnosing and fixing Pulumi state drift when `pulumi refresh` doesn't behave as expected. Covers real root causes, verification steps, and a war story from production.
Ansible Task Not Idempotent: Changed Every Run
An Ansible task that reports 'changed' on every run is breaking idempotency. This guide covers real-world causes beyond check_mode, from missing diff to transient state in shell commands.
Istio Sidecar Envoy 503: Debugging Upstream Connection Failures
A systematic guide to diagnosing 503 responses from Istio sidecar proxies, covering upstream cluster issues, TLS mismatch, and routing misconfigurations.
Linkerd mTLS Handshake Failures: A Practical Debugging Guide
Linkerd mTLS connections failing? This guide covers diagnosing broken TLS handshakes, certificate mismatches, and policy misconfigurations in Kubernetes.
Debugging SWC Transform Errors: Syntax Errors in Rust-Based JS/TS Transforms
A practical guide to diagnosing and fixing syntax errors when using SWC for JavaScript/TypeScript transforms. Covers common causes like mismatched decorators, unsupported syntax, and misconfigured .swcrc.
Metro Bundler 'Unable to Resolve Module' — Real Debugging & Fix Strategy
A practical guide to debugging Metro Bundler's 'Unable to resolve module' errors in React Native projects, covering cache, aliases, symlinks, and native module misconfigurations.
Long-form thinking on debugging habits, observability, and the systems around the bug.
How to Read Error Messages: A Debugging Protocol
Most engineers skim error messages and miss the signal. Here's a repeatable protocol for extracting maximum information from stack traces, log lines, and crash dumps — with a real incident walkthrough.
When to Escalate a Bug: A Decision Framework for Junior and Mid-Level Engineers
A practical framework for junior and mid-level engineers to decide when to escalate a bug, with real-world examples and criteria beyond time spent.
Debugging vs. Firefighting: Why Treating Production Incidents as Debugging Sessions Fails
When production goes down, your brain wants to debug. That instinct costs you hours. Here's why firefighting requires a fundamentally different approach, and the specific process I use to switch modes.
Writing an Incident Runbook That Actually Gets Used in Production
A runbook isn't a document—it's a tool. Here's how to write one that reduces MTTR and doesn't embarrass you during the next PagerDuty alert.
Debugging a production incident with your boss on Slack: staying rational when everything is on fire
A personal account of debugging a cascading Redis failure while the VP of Engineering watched, and the mental models that kept the fix from turning into a rollback.
Reading Distributed Traces to Find Latency: A Field Guide
Tracing tools generate a firehose of data. Here's how to filter the signal from the noise and actually find the root cause of high latency.