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.
How to Read Error Messages: A Debugging Protocol
Most engineers skim error messages and miss the signal. Here's a repeatable protocol for extracting maximum information from stack traces, log lines, and crash dumps — with a real incident walkthrough.
When to Escalate a Bug: A Decision Framework for Junior and Mid-Level Engineers
A practical framework for junior and mid-level engineers to decide when to escalate a bug, with real-world examples and criteria beyond time spent.
Debugging vs. Firefighting: Why Treating Production Incidents as Debugging Sessions Fails
When production goes down, your brain wants to debug. That instinct costs you hours. Here's why firefighting requires a fundamentally different approach, and the specific process I use to switch modes.
Writing an Incident Runbook That Actually Gets Used in Production
A runbook isn't a document—it's a tool. Here's how to write one that reduces MTTR and doesn't embarrass you during the next PagerDuty alert.
Debugging a production incident with your boss on Slack: staying rational when everything is on fire
A personal account of debugging a cascading Redis failure while the VP of Engineering watched, and the mental models that kept the fix from turning into a rollback.
Reading Distributed Traces to Find Latency: A Field Guide
Tracing tools generate a firehose of data. Here's how to filter the signal from the noise and actually find the root cause of high latency.