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.
3 playbooks in Backend & APIs
Debugging Retry Bugs
Retry issues often hide the first failure and create duplicate work.
Debugging Idempotency Bugs
How to debug duplicate writes when clients, webhooks, or workers retry after ambiguous failures.
Debugging Payment Races
How to reason about duplicate charges, concurrent refunds, and payment workflow compensation.
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.
GraphQL Subscription Not Receiving Events: A Field Guide to Silent Failures
Debug why your GraphQL subscription stops receiving events. Covers transport, resolver, and infrastructure causes with concrete commands.
Debugging GraphQL Schema Stitching Federation Errors
A hands-on guide to diagnosing and fixing schema stitching and federation errors in GraphQL microservices, covering type conflicts, directive mismatches, and gateway misconfigurations.
DNS Caching Stale Records: Why TTL Is Ignored and How to Fix It
A practical guide to debugging cases where DNS resolvers serve stale records past their TTL, covering common causes like resolver caches, stub resolvers, and low TTLs.
Debugging HTTP Keep-Alive Connection Reset by Peer
A practical guide to diagnosing and fixing 'connection reset by peer' errors on HTTP keep-alive connections, covering server, proxy, and network causes.
Debugging AWS AppSync Resolver Mapping Errors
A practical guide to diagnosing and fixing VTL and JavaScript mapping errors in AWS AppSync resolvers, covering common pitfalls and production debugging techniques.
Long-form thinking on debugging habits, observability, and the systems around the bug.
Debugging Third-Party API Issues: A Systematic Approach
A practical guide to diagnosing and fixing third-party API integration problems, with real-world examples and a step-by-step debugging framework.
Debugging Webhook Delivery Failures: What the Logs Don't Tell You
HTTP 200 doesn't mean your webhook was processed. A practical guide to the network and middleware layers that silently drop webhooks.
Debugging HTTP Headers with curl: From Basic Flags to Packet-Level Inspection
A practical guide to inspecting HTTP request and response headers with curl, covering basic flags, debugging tricky issues, and understanding what your headers are really doing.
Debugging WebSocket Real-Time Features: Packet Loss, Reconnect Storms, and Silent Failures
WebSocket debugging goes beyond console.log. I cover packet capture with tcpdump, reconnect backoff strategies, and a war story about a silent failure that took down a production chat feature.
Rest API Design Mistakes That Inject Bugs Into Your System
Most API bugs aren't in the implementation—they're baked into the contract. Here are the design errors I've seen cause the most production incidents.
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.