Thinking / Edge Case Inc.
Small incident. A fictional software company. Real engineering questions. Follow an unexpected behavior through the runtime, the architecture, and the people who depend on it.
Case 001 / Runtime trace Observe → explain
Listener A · still active Listener B · registered
02 / The symptom Two effects in the interface. The transport reconnected. Did the previous subscription leave?
01 open case
Each case follows one mechanism through four perspectives: production behavior, architecture, product workflows, and business value.
Fictional team · real trade-offs 01 / Case directory
Start with the symptom. The opening investigation begins with a duplicate WebSocket effect. Follow the mechanism before deciding where the fix belongs.
CASE 001 Series opening
WebSocket lifecycle and duplicate processing
The event that happened twice A harmless-looking reconnection crosses runtime behavior, ownership boundaries, user workflows, and business correctness.
Follow the investigation What you’ll investigate
Fox Production engineering Trace listener registration, cleanup, reconnection, and the evidence that separates transport duplication from client duplication.
Bear Architecture in practice Decide which boundary owns the connection and how one active subscription becomes an enforceable invariant.
Rabbit Product engineering Follow the duplicate event into notifications, user decisions, task state, and the meaning of an action in progress.
Hedgehog Business value Test the explanation against observable evidence and connect technical duplication to support cost and trust.
Read the series on LinkedIn 02 / The investigators
Different questions. The characters make invisible behavior easier to discuss. Four follow the opening case; Owl joins when AI or automation changes the question.
01 Runtime behavior
Fox What actually ran? Traces listeners, cleanup, and reconnection before naming the cause.
02 System boundaries
Bear Who owns the lifecycle? Looks for the boundary that can enforce one active subscription.
03 User workflows
Rabbit What did the person experience? Follows duplicate effects into notifications, task state, and decisions.
04 Evidence & value
Hedgehog What can we prove? Tests the explanation against observable behavior and its consequences for trust.
05 AI & automation
Owl What changes when we automate? Joins investigations where AI changes the mechanism or the responsibility.
03 / Keep following the reasoning
From an incident Explore the architectural decisions behind product systems, or use the Engineering Wiki to study the underlying concepts.
Read the architecture essays Explore the Engineering Wiki