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.
18 playbooks · 509 guides · 96 articles · 13 linked practice labs ·skip to practice
Fast pattern recognition for the production failures engineers see most often.
18 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 Cumulative Layout Shift (CLS): From Symptoms to Root Cause
A practical guide to diagnosing and fixing CLS issues in web performance, covering real-world causes, tools, and verification.
LCP Slow: How to Diagnose and Fix Largest Contentful Paint Issues
A practical guide to diagnosing and fixing slow Largest Contentful Paint (LCP) in production web apps.
Intersection Observer Callback Not Firing: Debugging Silent Failures
A practical guide to diagnosing why your IntersectionObserver callback never fires — covering root causes from thresholds to root margins, with real debugging commands and war stories.
Service Worker Serving Stale Cache: Diagnose and Fix
A guide to debugging when a service worker returns stale cached responses instead of fresh data from the network.
SAML SSO Login Fails After IdP Metadata Update
A complete debugging guide for SAML SSO login failures, covering certificate rotation, assertion validation, and clock skew issues.
OpenID Connect ID Token Validation Failure Debugging
A practical guide to diagnosing and fixing OpenID Connect ID token validation failures, covering signature verification, expiration, issuer mismatch, and audience checks.
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.