02.1
CatalogEvents registered once
Event types are declared with their schema and validated on publish, so a typo in a payload is caught where it is written.
Schema-checked
#What it is
Relay delivers webhooks. Tenant-scoped endpoints, event types defined at runtime, signed deliveries, retries, and a dead-letter queue you can replay, all as a library you import.
#What it does
- Dynamic event types registered at runtime with optional JSON Schema validation, so a new event does not require a deploy of the delivery layer.
- HMAC-SHA256 signatures on every delivery, with a signature package receivers can use to verify.
- Exponential backoff: 5s, 30s, 2m, 15m, 2h by default. What still fails lands in the DLQ.
- Per-endpoint rate limiting through a token bucket, so one slow customer endpoint cannot back up the queue for everyone.
- Glob event subscriptions: an endpoint subscribes to order.* rather than enumerating.
- Admin HTTP API with full CRUD over event types, endpoints, events, deliveries and DLQ replay.
- OpenTelemetry and Prometheus: a trace span per delivery, plus counters, latency histograms and gauges.
#The part people underestimate
Replay is the feature customers actually ask about, and it is only useful if deliveries are stored with enough fidelity to reconstruct exactly: same body, same signature, same headers. Storing a summary instead of the payload is a decision that looks reasonable until the first support request.