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 Node.js Cluster Module Worker Crashes
A hands-on guide to diagnosing and fixing worker crashes in Node.js cluster mode, covering uncaught exceptions, memory leaks, and IPC failures.
Debugging TypeScript Generic Type Constraint Errors
A practical guide to diagnosing and fixing TypeScript errors when generic type parameters violate their constraints, with real-world debugging strategies and a war story.
Mapped Types Returning 'never' or 'unknown' — What Your IDE Won't Tell You
A field guide for when mapped types silently collapse to 'never' or 'unknown', covering conditional checks, key remapping, and distributive conditional types.
JavaScript Closure Stale Variable Inside Loop
A debugging guide for the classic JavaScript closure-in-loop bug where callbacks capture the final value of a loop variable instead of each iteration's value.
TypeScript Discriminated Union Type Narrowing Not Working
A practical debugging guide for when TypeScript's discriminated union type narrowing fails due to common pitfalls like excess property checks, optional discriminants, and type assertions.
Debugging Prototype Chain Inheritance Bugs in JavaScript
A guide to diagnosing and fixing subtle bugs caused by shared state and unintended property shadowing in JavaScript prototype chains.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Debugging CSS Layout Issues: A Systematic Approach to Fixing Broken Layouts
A practical, step-by-step system for diagnosing and fixing CSS layout bugs — from overflow and collapsing margins to flexbox and grid misbehavior. Includes real DevTools workflows and a war story from production.
Debugging Accessibility Violations: A Systematic Approach from Audit to Fix
A practical guide to identifying, triaging, and fixing accessibility violations in web applications, covering automated tools, manual testing techniques, and common pitfalls.
Find the Real Cause of a Slow Page: A Profiling Protocol for Engineers
A practical protocol for profiling web page performance — not a list of metrics, but a repeatable process for finding what actually slows down your users.
Tracking Down Memory Leaks in Browser JavaScript: A Practical Field Guide
Memory leaks in the browser are subtle and hard to reproduce. This guide covers practical techniques to detect, isolate, and fix them using Chrome DevTools, heap snapshots, and allocation timelines.
Why Your 60fps Animation Stutters: A Deep Dive Into the Browser Event Loop
The event loop isn't just about callbacks. It's about when and in what order the browser processes tasks, microtasks, and rendering. Here's what actually happens between frames.
Remote Debugging Mobile Devices at Scale: What Works and What Doesn't
Setting up remote debugging for iOS and Android devices involves more than just enabling Developer Mode. Here's what I've learned from debugging over 500 devices in production.