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.
React setState Called but State Not Updating: Real Debugging Steps
React state not updating after setState? Pinpoint hidden causes—like stale closures, async timing, or skipped re-renders—using targeted debugging tactics.
React.memo Fails to Prevent Re-render: Deep Props, Functions, and Traps
Debug React.memo not working: identify why supposedly memoized components still re-render, including deep prop equality, unstable functions, and context pitfalls.
Diagnosing 404s from Next.js API Routes That Should Exist
When your Next.js API route responds with a 404 despite existing, dig past simple typos. This guide covers real fixes, pitfalls, and non-obvious causes.
Next.js Middleware Not Executing on Expected Routes
Investigate why your Next.js middleware isn't firing as expected. This guide goes beyond basics and addresses subtle config, routing, and deployment issues.
Environment Variable Undefined at Runtime in Next.js Projects
Why and how Next.js environment variables end up undefined during runtime, including hidden build pitfalls. Step-by-step debugging for real production issues.
Diagnosing ‘React Hook Called Conditionally’ in Function Components
A hands-on guide to resolving errors from calling React hooks inside conditional blocks. Covers root causes, real-world mistakes, and validation steps.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Five Debugging Habits That Separate Seniors from Juniors
It's not tools. It's not years of experience. It's five repeatable habits that senior engineers do reflexively and juniors haven't built yet.
Why Your Production Logs Are Lying to You
Logs tell you what the code reported. They almost never tell you what actually happened. Here is the gap, and how to close it.
The Real Cost of Console.log Debugging (and What to Use Instead)
Every engineer reaches for console.log. Most do not think about what it costs — in time, in performance, or in production readiness. Here is the honest accounting.
Interpreting Stack Traces: Practical Steps for Faster Debugging
Stack traces can be dense, but reading them fluently accelerates triage and root cause analysis. This article explains how to extract actionable information, with real-world context.
Efficient Debugging with git bisect: Going Beyond Binary Search
This article explains how to incorporate git bisect into your debugging workflow, focusing on practical execution, automation, and common edge cases.
Applying Rubber Duck Debugging to Complex Engineering Problems
Rubber duck debugging isn’t just a quirky solo exercise. I’ll show how explaining code out loud surfaces misunderstandings and reduces wasted team cycles.