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.
Kubernetes pod CrashLoopBackOff: how to debug crashing pods
Your pod starts, crashes, restarts, crashes again. The CrashLoopBackOff status means Kubernetes is giving up. The pod logs hold the answer.
SSL certificate error after deployment: how to debug TLS issues
Your site was working with HTTPS. After a deployment, browsers show SSL errors. The certificate expired, was not renewed, or the domain changed.
Frontend build works locally but fails on Vercel or Render: how to debug it
Your build command succeeds locally but fails when Vercel or Render runs it. The platform has a different Node version, memory limit, or build settings.
API timeout: how to debug request timeout issues
Your API endpoint returns a timeout error. The request takes longer than the configured timeout, but the operation might have succeeded silently on the server.
Duplicate emails sent by retry bug: how to debug it
Your email service retries a failed send, but the first send actually succeeded. Users get two, three, or ten copies of the same email.
Pagination off by one bug: how to debug pagination errors
Your paginated list skips the first item, shows the last item twice, or has an empty last page. The offset, limit, or page calculation is off by one.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Debugging Production Issues Without a Debugger: Approaches That Work
Attaching an interactive debugger in production is usually impossible. Here’s how I gather signal, reproduce issues, and restore service using other techniques.
Writing Bug Reports That Developers Appreciate
A good bug report is more than a template. Learn which details actually move the needle, and which common 'best practices' waste developer time.
Assert Statements: Where They Help and Where They Hurt
Assert statements are a double-edged sword. Used correctly, they catch bugs early and document invariants. Used carelessly, they can mask failures and create security holes. Here's how to wield them effectively.
Defensive Logging: Patterns for Surviving Production Data Rot
Most logging advice stops at 'log more'. Here's how to log defensively—handling nulls, encoding, PII, and context propagation before they rot your observability pipeline.
Debuggers vs Console.log: Why I Stopped Using Print Statements for Debugging
Print statements are the duct tape of debugging. They work for trivial issues, but for race conditions, async flows, or deep call stacks, a debugger saves hours. Here's what I learned after years of using both.
Treating Bugs as Hypotheses: How the Scientific Method Fixes Debugging
Frustrated by flailing through logs? The scientific method turns debugging into a reproducible process. Here's how to formulate hypotheses, design experiments, and isolate root causes with confidence.