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.
Next.js Image Component Fails to Optimize Images
Diagnose and fix root causes when Next.js <Image> skips optimization. Covers config, domains, loader issues, and CDN missteps beyond the basics.
React List Rendering: Diagnosing and Fixing Key Prop Warnings
How to debug and resolve React's list key prop warnings, including subtle runtime issues beyond console noise. Concrete steps, root causes, and real-world incident.
Next.js Static Site Generation Build Failures: Diagnosing getStaticProps and getStaticPaths Issues
Concrete diagnosis and fixes for Next.js static generation (SSG) build failures, covering getStaticProps, getStaticPaths, missing data, and non-obvious traps.
Diagnosing `ref.current` Is Null in React
A practical guide to tracing and fixing cases where a React ref's `current` is unexpectedly null, including async pitfalls and strict mode quirks.
Diagnosing and Resolving Next.js Server Action Errors
Pinpoint and fix errors in Next.js server actions, focusing on non-obvious causes like serialization and environment mismatches.
Diagnosing React Router Infinite Redirect Loops
How to fix and prevent infinite redirect loops in React Router—pinpoint the logic errors, misconfigurations, and unexpected auth flows that cause them.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Logs, Traces, and the Lies They Tell: Debugging a Stuck Queue in Production
A single stuck queue brought down an entire checkout flow. Here's how we traced the failure across services, what the logs didn't say, and the tools that finally showed the truth.
Pair Debugging: How to Debug Together Without Killing Each Other
Pair debugging sounds great on paper. In practice, it's easy to step on each other's toes, go silent, or fight over the keyboard. Here's how to make it work.
Debugging with AI Tools: What Worked and What Didn't in Production
After a year of using GPT-4, Copilot, and Claude to hunt production bugs, here's what actually helped — and what sent me down dead ends.
How to Debug Legacy Code Without Losing Your Mind
A pragmatic approach to debugging code you didn't write, with techniques for tracing execution, isolating side effects, and making safe edits.
Debugging Feature Flag Rollouts: Tracing the Live-at-5 Incident
A misconfigured feature flag triggered a cascading failure in production. Here's how we traced the root cause and built a better debugging toolkit.
How to Ask for Debugging Help Without Wasting Everyone's Time
Asking for debugging help is a skill. Here's how to provide enough context, show your work, and frame the problem so others can actually help you.