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 SQS Messages Going to DLQ: Root Causes and Fixes
Troubleshoot why SQS messages are routed to dead-letter queues. Covers redrive policy misconfig, consumer timeouts, payload issues, and IAM pitfalls with concrete debugging steps.
Debugging Elasticsearch Slow Queries: From Shard Contention to Circuit Breakers
A field guide to diagnosing and fixing Elasticsearch slow queries, covering shard contention, hot threads, circuit breakers, and real-world mitigation strategies.
Elasticsearch Yellow Cluster: Unassigned Shards Deep Debug
A focused guide for diagnosing yellow cluster status caused by unassigned shards, covering allocation explain, disk thresholds, and node recovery.
GraphQL Subscription Not Receiving Events: A Field Guide to Silent Failures
Debug why your GraphQL subscription stops receiving events. Covers transport, resolver, and infrastructure causes with concrete commands.
Debugging GraphQL Schema Stitching Federation Errors
A hands-on guide to diagnosing and fixing schema stitching and federation errors in GraphQL microservices, covering type conflicts, directive mismatches, and gateway misconfigurations.
Detached DOM Tree Memory Leak: Hunting Ghost Nodes in the Browser
A production debugging guide for browser detached DOM node memory leaks: how to find them, fix them, and prevent them in React/Angular/Vanilla JS apps.
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.