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.
Diagnosing Nuxt Hydration Mismatch Errors in Production
Hydration mismatch errors in Nuxt apps break SSR interactivity and can be tough to pinpoint. This guide walks through investigating, reproducing, and fixing these.
Vue Router Navigation Guard Blocking Route Transitions
Diagnose and resolve Vue Router navigation guards unexpectedly blocking route changes. Covers subtle mistakes and issues beyond standard docs.
Why Your Vue Composition API ref Isn’t Reactive
Vue’s Composition API refs sometimes fail to trigger reactivity. This guide covers subtle causes, practical debugging, and real-world fixes for non-reactive refs.
Diagnosing Missing Cookies in Nuxt SSR Server Context
Nuxt SSR often fails to read cookies server-side if headers are misrouted or missing. This guide shows where things break and how to reliably retrieve cookies in SSR.
Vue Watcher Causing Infinite Render Loop
Vue watch handlers sometimes trigger infinite update cycles. This guide detangles the real causes, not just the basics, and shows how to fix them.
Pinia Store State Not Persisting Across Page Reloads
Diagnosing and fixing issues when your Pinia store state resets on page reloads—even with plugins or localStorage configured.
Long-form thinking on debugging habits, observability, and the systems around the bug.
How to Reproduce a Flaky Test: From CI Logs to Reliable Failure
A practical guide to turning intermittent test failures into reliably reproducible bugs, with techniques ranging from loop testing to thread sanitizers.
Property-Based Testing: Finding the Off-by-One That Lived in Production for 18 Months
A concrete story of how switching from example-based tests to property-based tests caught a timing bug that had survived code review, QA, and 18 months of production traffic.
How We Reduced End-to-End Test Flakiness by 80% with Deterministic Seeding
After months of chasing intermittent failures in our CI pipeline, we implemented a three-part strategy — deterministic seeding, isolated state per test, and a structured retry budget — that cut flaky end-to-end test failures by 80%.
Snapshot Testing: The 5 Hidden Failure Modes That Will Break Your CI
Snapshot tests seem like a safety net, but they often hide real bugs, bloat diffs, and silently break your CI. Here are the five failure modes I've seen in production and how to fix them.
Testing Async Code: Avoiding Flakiness and False Positives in JavaScript
Async testing is full of traps: unhandled rejections, race conditions, and tests that pass when they shouldn't. Here's how to write reliable async tests in JavaScript.
Testing Error Handling Code Paths: A Practical Approach
Error handling code is often the least tested and most brittle. Here's how to cover those paths with fault injection, mocks, and chaos engineering.