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.
Python Decorator Losing Function Metadata: __name__, __doc__, and __wrapped__
A practical debugging guide for when Python decorators strip function metadata like __name__, __doc__, and __module__, and how using functools.wraps or manual reassignment fixes it.
Python Context Manager Not Releasing Resource: Debugging Guide
A debugging guide for context managers in Python that fail to release resources, covering common causes like exceptions, reference cycles, and generator cleanup issues.
Debugging Mutable Default Arguments in Python Dataclasses
A practical guide to identifying and fixing the mutable default argument bug in Python dataclasses, with real-world debugging steps and a production war story.
Python logging not showing output: Why your log messages vanish
A practical guide to diagnosing silent loggers in Python, covering root logger, handler levels, propagation, and common misconfigurations that cause output to disappear.
Debugging Pytest Fixture Scope Mismatches
A practical guide to diagnosing and fixing fixture scope conflicts in pytest, covering shared state, teardown order, and concurrency issues.
Python Mock patch() Wrong Target: Why Your Mock Isn't Mocking
A debugging guide for when unittest.mock.patch doesn't work because the target string points to the wrong module path.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Five Debugging Habits That Separate Seniors from Juniors
It's not tools. It's not years of experience. It's five repeatable habits that senior engineers do reflexively and juniors haven't built yet.
Why Your Production Logs Are Lying to You
Logs tell you what the code reported. They almost never tell you what actually happened. Here is the gap, and how to close it.
The Real Cost of Console.log Debugging (and What to Use Instead)
Every engineer reaches for console.log. Most do not think about what it costs — in time, in performance, or in production readiness. Here is the honest accounting.
Interpreting Stack Traces: Practical Steps for Faster Debugging
Stack traces can be dense, but reading them fluently accelerates triage and root cause analysis. This article explains how to extract actionable information, with real-world context.
Efficient Debugging with git bisect: Going Beyond Binary Search
This article explains how to incorporate git bisect into your debugging workflow, focusing on practical execution, automation, and common edge cases.
Applying Rubber Duck Debugging to Complex Engineering Problems
Rubber duck debugging isn’t just a quirky solo exercise. I’ll show how explaining code out loud surfaces misunderstandings and reduces wasted team cycles.