Event-Driven Notification Hub
The complete system record. Choose the proof lens that fits your role.
Choose The Proof Lens
One system record, three reader paths.
One Notification Service for Every Project in the Portfolio
Product teams replace 8-10 hours of notification setup per app with one HTTP call, shared templates, preferences, and delivery tracking.
Architectural Brief: Event-Driven Notification Hub
Kafka consumer sits behind a USE_KAFKA flag because Redpanda burns 150MB on a 1GB VPS. Direct HTTP ingestion and Kafka converge on one pipeline.
The Signing Bug You Cannot See Until a Tenant Tries to Verify You
The Hub and the tenant hashed the same JSON payload to different signatures. JSON.stringify key order is non-deterministic, so callback verification silently failed.
The Cursor Pagination That Worked Until Five Rows Shared a Timestamp
Five suppression rows seeded in one transaction shared a microsecond-level timestamp. Cursor pagination returned three of them. Date.toISOString lost the rest.
The Per-Tenant Rate Limit That Wasn't Per-Tenant
Per-tenant rate limit silently capped every tenant at the default 200/minute. The rate check ran before auth populated the tenant on the request.
Why I Designed the Whole System Around Kafka and Then Deployed Without It
Redpanda burned 150-200MB of a 1GB VPS before the application even started. The Kafka consumer sits behind a flag until the RAM budget grows.
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