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 AWS API Gateway 502 Bad Gateway Errors
A practical guide to diagnosing and fixing 502 Bad Gateway errors from AWS API Gateway, covering common causes like VPC link misconfigurations, integration timeouts, and backend response formatting.
AWS RDS Connection Refused: Security Group Debug Guide
A practical guide to diagnosing and resolving RDS connection refused errors caused by security group misconfigurations, with real commands and war stories.
Custom Metrics Not Appearing in AWS CloudWatch: A Debugging Guide
Diagnose why your custom CloudWatch metrics are not showing up. Covers common causes like namespace mismatch, timestamp issues, and IAM permissions.
Debugging AWS SQS Message Visibility Timeout Causing Duplicate Processing
A practical guide to diagnosing and fixing duplicate message processing caused by visibility timeout misconfiguration in AWS SQS.
AWS CloudFront Serving Stale Content – Debugging Cache Invalidation Failures
A hands-on guide to diagnosing and fixing stale content served by CloudFront when cache invalidations don't work as expected.
Debugging AWS VPC Security Group Traffic Blocked
Step-by-step guide to diagnosing and fixing traffic blocked by AWS security groups. Covers common misconfigurations, hidden gotchas, and verification techniques.
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.