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.
Configuration Options Not Binding in .NET: How to Debug
A practical guide to debugging .NET configuration binding failures, covering real-world causes like casing mismatches, missing sections, and premature validation.
Elixir GenServer call timeout: How to find and fix the real cause
A hands-on guide for debugging Elixir GenServer call timeouts: from symptoms and root causes to specific fixes and verification steps, with a real incident walkthrough.
Phoenix LiveView assign not updating UI: Debugging Stale State
A practical guide to debugging Phoenix LiveView UI that doesn't update after an assign change. Covers socket diffs, Ecto schema reloads, and dead-end pitfalls.
Debugging Ecto N+1 Preload Queries in Elixir
Identify and fix N+1 query problems caused by Ecto preload misuse in Elixir/Phoenix applications.
Elixir Process Mailbox Overflow: How to Diagnose and Fix Unbounded Message Accumulation
Diagnose and fix Elixir process mailbox growth that causes memory pressure, latency spikes, and crashes. Covers OTP mailbox internals, redbug, recon, and practical fixes.
Kotlin Coroutine Not Cancelling: Debugging Stuck Jobs
A practical guide to debugging Kotlin coroutines that ignore cancellation, covering common pitfalls like blocking calls, uncooperative suspend functions, and improper scope management.
Long-form thinking on debugging habits, observability, and the systems around the bug.
The Art of the Minimal Reproducible Example: A Debugging Superpower
A minimal reproducible example (MRE) is more than just a snippet — it's a tool that isolates the bug, saves time, and gets you faster answers. Here's how to build one that works, with a real-world war story.
Retry Storms: When Retries Make a Cascading Failure Worse
Retries seem like a safety net, but in a distributed system under load they can turn a small hiccup into a full outage. Here's how retry storms form and what to do about them.
Caching Bugs Are the Worst: A Postmortem on Stale Data Disasters
A deep dive into the most insidious caching bugs, with real postmortems and practical patterns to avoid stale-data disasters.
Observability vs. Monitoring: Why Your On-Call Rotation Still Wakes You Up at 3 AM
Monitoring tells you something is broken. Observability lets you figure out why—without guessing, without SSH, without restarting the pod.
Debugging Flaky Tests for Good: A Systematic Approach to Root Cause Analysis
Flaky tests waste time and erode trust. Here's how to find and fix the actual root cause instead of just rerunning.
Idempotency Keys: The Safety Net Your Payment API Needs
How idempotency keys prevent double charges, lost refunds, and data corruption in payment APIs. With real-world examples and edge cases you haven't considered.