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.
PostgreSQL Full-Text Search Returns No Results
Debug why PostgreSQL full-text search returns empty results despite seemingly correct queries and indexes. Covers tsvector/tsquery mismatches, configuration issues, and silent failures.
PostgreSQL Replication Lag Too High – Diagnosis and Fixes
A practical guide to diagnosing and fixing high replication lag in PostgreSQL. Covers common causes like wal_keep_segments, network bottlenecks, and standby query conflicts.
PostgreSQL Table Bloat: When VACUUM Stops Working
A deep-dive into PostgreSQL table bloat caused by VACUUM failing to reclaim space due to long-running transactions, replication slots, or dead tuple accumulation.
Postgres ALTER TYPE Enum Migration Fails: Cannot Add New Value Inside a Transaction Block
A guide to debugging and fixing PostgreSQL 'ALTER TYPE ... ADD VALUE' failures during migrations, including transaction block and ordering issues.
Postgres CTE Performance: Why Your Query Suddenly Slowed Down
A practical guide to diagnosing and fixing performance issues with PostgreSQL Common Table Expressions (CTEs), focusing on the optimizer fence problem and materialization.
Postgres Trigger Not Firing: Debugging Silent Failures
A systematic approach to debug Postgres triggers that don't execute, covering common pitfalls like statement-level vs row-level, trigger visibility, and silent errors.
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.