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.
IndexedDB Data Not Persisting: Silent Writes and Missing Transactions
When IndexedDB writes appear to succeed but data vanishes on reload, the root cause is almost always a mishandled transaction, quota error, or blocked upgrade. This guide exposes the real-world failures behind 'not storing data' and how to trace them.
Web Worker Communication Failures: Why postMessage Stops Working
A deep dive into why postMessage between main thread and web workers silently fails, covering cloning errors, closed ports, and structured clone algorithm limits.
Debugging Ruby Bundler Gem Conflict Errors
A practical guide to diagnosing and resolving gem dependency conflicts in Ruby Bundler, with real commands and war stories.
Rails Database Migration Error: Failed to Add Column Due to Lock Wait Timeout
A practical guide to diagnosing and fixing Rails migration failures caused by lock wait timeouts, schema inconsistencies, and database deadlocks in production.
Detecting and Fixing ActiveRecord N+1 Queries in Rails
A practical guide to identifying, diagnosing, and eliminating N+1 queries in Rails applications using Bullet, rack-mini-profiler, and eager loading.
How to Debug a Failing Sidekiq Job That Keeps Retrying
A practical guide to diagnosing and fixing Sidekiq jobs that fail and retry endlessly—covers real causes, commands, and fixes.
Long-form thinking on debugging habits, observability, and the systems around the bug.
The Debugging Mindset: A Systematic Method for Finding Root Causes
A repeatable, hypothesis-driven approach to debugging that works for intermittent failures, performance regressions, and production incidents.
Analyzing a Core Dump: What to Do When Your Process Goes Silent
A core dump is your process's last scream. Here's how to make it talk.
Timeouts Every Engineer Gets Wrong (and How to Fix Them)
Most timeout bugs aren't logic errors — they're configuration failures. Here's how to stop treating timeouts as magic numbers and start engineering them deliberately.
Backpressure in Streaming Systems: When Your Pipeline Fights Back
Backpressure is the system's way of saying 'slow down.' Ignore it and you get OOM crashes, silent data loss, or cascading failures. Here's how to design for it.
Finding Memory Leaks Step by Step: A Systematic Approach
Memory leaks are the silent killers of long-running services. Here's a repeatable process to hunt them down, from heap dumps to production monitoring.