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.
Pulumi State Drift: How Refresh Lies and What to Actually Do
A hard-nosed guide to diagnosing and fixing Pulumi state drift when `pulumi refresh` doesn't behave as expected. Covers real root causes, verification steps, and a war story from production.
Ansible Task Not Idempotent: Changed Every Run
An Ansible task that reports 'changed' on every run is breaking idempotency. This guide covers real-world causes beyond check_mode, from missing diff to transient state in shell commands.
Istio Sidecar Envoy 503: Debugging Upstream Connection Failures
A systematic guide to diagnosing 503 responses from Istio sidecar proxies, covering upstream cluster issues, TLS mismatch, and routing misconfigurations.
Linkerd mTLS Handshake Failures: A Practical Debugging Guide
Linkerd mTLS connections failing? This guide covers diagnosing broken TLS handshakes, certificate mismatches, and policy misconfigurations in Kubernetes.
Debugging SWC Transform Errors: Syntax Errors in Rust-Based JS/TS Transforms
A practical guide to diagnosing and fixing syntax errors when using SWC for JavaScript/TypeScript transforms. Covers common causes like mismatched decorators, unsupported syntax, and misconfigured .swcrc.
Metro Bundler 'Unable to Resolve Module' — Real Debugging & Fix Strategy
A practical guide to debugging Metro Bundler's 'Unable to resolve module' errors in React Native projects, covering cache, aliases, symlinks, and native module misconfigurations.
Long-form thinking on debugging habits, observability, and the systems around the bug.
How to Debug a Regression: A Practical Walkthrough
A practical, step-by-step guide to finding and fixing regression bugs, with real-world examples and concrete commands you can run today.
The Cost of Not Reproducing Bugs: Why Local Debugging Saves Hours
Skipping local reproduction leads to wasted hours, broken deploys, and frustrated teams. Here's why it's non-negotiable and how to do it right.
Debugging an Unfamiliar Codebase: A Systematic Approach
A repeatable process for debugging code you didn't write — with specific techniques, tooling choices, and a war story from a production outage at 2 AM.
5 Questions to Ask Yourself Before Filing a Bug Report
A senior engineer's pre-flight checklist for bug reports — forged in the fire of a production incident that turned a 5-minute fix into a 3-hour hunt.
Binary Search for Bugs: Cutting Down Bisection Time with git bisect run
Automating git bisect with a script turns days of manual hunting into minutes. Here's how to build a reliable bisection harness for your codebase.
Reading a Call Stack: What Each Frame Actually Tells You
A call stack shows you the path your code took to crash. But most developers only look at the top frame. Here’s how to read the whole thing — including async traces, native frames, and minified code.