Reliability engineering · 2026 · Solo — research, systems design, build, verification
Retry Yard
An interactive virtual-time switchyard for reviewing webhook retry policy before shipping a production worker.
The problem
Webhook retry behavior is usually spread across queue settings, worker code, HTTP response handling, and idempotency storage. That makes policy interactions difficult to review before implementation. Retry Yard compresses those concerns into one deterministic local simulation without sending payloads, calling endpoints, or claiming parity with a specific provider.
Architecture
Key decisions
Use virtual time instead of timers
Every run resolves synchronously into an auditable trace. The same seed and policy produce the same schedule, which makes retry behavior reproducible in tests and reviewable in the interface.
Model reliability concerns together
Backoff, jitter, Retry-After, idempotency, permanent failure, and maximum-attempt exhaustion share one state machine so their interactions are visible rather than explained in isolation.
Send no webhook traffic
The simulator requests neither endpoints nor payloads. It is a bounded planning instrument for policy review, not a vendor emulator or production delivery worker.
Make causality the interface
The safety-orange control tower, envelope switchyard, and selectable docket expose why each attempt moved, waited, succeeded, deduplicated, or entered the dead-letter bay instead of reducing the result to summary cards.