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 HPACK Errors in HTTP/2 Header Compression
A practical guide to diagnosing and fixing HTTP/2 header compression errors caused by HPACK implementation bugs, oversized headers, or compression context mismatches.
Nginx Upstream 503 Service Unavailable: A Production Debugging Guide
A practical guide to diagnosing and fixing Nginx 503 errors caused by upstream failures, including connection limits, timeouts, and health check misconfigurations.
Debugging Nginx Rate Limiting 503 Errors
A practical guide to diagnosing and fixing 503 errors caused by Nginx rate limiting, with concrete commands and real-world scenarios.
SameSite Cookie Attribute Blocking Requests: Debugging Guide
A practical guide to diagnosing and fixing request failures caused by the SameSite cookie attribute, including cross-site and same-site nuances.
CSRF Token Validation Failed: Real-World Debugging Guide
A practical debugging guide for CSRF token validation failures in web applications, covering root causes, diagnosis, and fixes beyond the textbook.
Content Security Policy Blocking Resource: Debugging and Fixing CSP Violations
A direct guide to diagnosing and fixing CSP violations when resources like scripts, styles, or images are blocked by Content Security Policy headers.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Sentry Error Monitoring: A Practical Setup Guide from a Production Outage
A step-by-step setup guide for Sentry error monitoring, covering source maps, release tracking, grouping rules, and alerting — with a real story of a production outage that taught us the hard way.
Reading Prometheus Alert Rules: A Practical Reference for Debugging Firing Alerts
Alert rules look straightforward until you're staring at a firing alert at 3 AM. This post covers the structure, common traps, and how to extract actionable intent from any rule.
Debugging Network Issues with Chrome DevTools: Timing, Waterfalls, and Hidden Columns
A practical guide to diagnosing slow requests, stalled connections, and caching bugs using the Network tab's non-obvious features.
Finding Jank in React Apps with Chrome DevTools Performance Tab
A practical walkthrough of the Performance tab for diagnosing frame drops and long tasks in React apps, with a real debugging story.
Using Breakpoints Effectively: Beyond Step and Continue
Most engineers know F9 to set a breakpoint and F5 to run. But breakpoints have hidden superpowers — conditional, logpoint, hit-count, and data breakpoints — that can cut debugging time in half. Here's how to use them with real examples.
Conditional Breakpoints: When and How to Use Them Beyond the Basics
Conditional breakpoints stop only when a specific condition is true, reducing noise in loops and high-frequency code. Here's how to wield them in Chrome DevTools, VS Code, and IntelliJ, plus a war story about a subtle race condition.