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.
Debugging 'JWT Invalid Signature' Failures in Production
JWT invalid signature errors often stem from key mismatches, encoding quirks, or unnoticed library pitfalls. This guide details concrete, real-world debugging steps.
Debugging UnhandledPromiseRejection in Node.js Applications
How to identify, isolate, and fix UnhandledPromiseRejection warnings in Node.js, with specific steps and sample incidents.
Diagnosing and Fixing Next.js Build Failures
A practical guide to debugging Next.js build errors, with actionable steps, overlooked root causes, and real-world war stories.
Diagnosing Silent Failures and Deadlocks in Python Asyncio
A precise engineering guide for tracking down deadlocks, silent failures, and missed awaits in Python asyncio — beyond the usual print debugging.
Diagnosing Broken Networking in Docker Containers
A practical guide for tracking down and fixing broken networking between Docker containers, with real commands, root causes, and verification steps.
Diagnosing React Context Unnecessary Re-renders Impacting Performance
React Context misuse can silently trigger excess renders in deeply nested trees. Learn how to spot, diagnose, and fix these performance killers.
Long-form thinking on debugging habits, observability, and the systems around the bug.
How to Debug a Regression: A Practical Walkthrough
A practical, step-by-step guide to finding and fixing regression bugs, with real-world examples and concrete commands you can run today.
The Cost of Not Reproducing Bugs: Why Local Debugging Saves Hours
Skipping local reproduction leads to wasted hours, broken deploys, and frustrated teams. Here's why it's non-negotiable and how to do it right.
Debugging an Unfamiliar Codebase: A Systematic Approach
A repeatable process for debugging code you didn't write — with specific techniques, tooling choices, and a war story from a production outage at 2 AM.
5 Questions to Ask Yourself Before Filing a Bug Report
A senior engineer's pre-flight checklist for bug reports — forged in the fire of a production incident that turned a 5-minute fix into a 3-hour hunt.
Binary Search for Bugs: Cutting Down Bisection Time with git bisect run
Automating git bisect with a script turns days of manual hunting into minutes. Here's how to build a reliable bisection harness for your codebase.
Reading a Call Stack: What Each Frame Actually Tells You
A call stack shows you the path your code took to crash. But most developers only look at the top frame. Here’s how to read the whole thing — including async traces, native frames, and minified code.