BYLD Wealth — SIP Execution Saga (Choreography)

💬

MIA (User)

User Intent

"Start a monthly SIP of 25,000 in PPFAS Flexi Cap" — Claude parses intent, extracts fund, amount, frequency

sip.intent.created

~2s (Claude SSE)

✅

Advisory

Validate & Confirm

Risk-profile check, goal alignment validation, suitability score. MIA presents confirmation card with fund details

sip.validated

~0.5s

💳

Payments

Create Mandate

Razorpay UPI/eNACH mandate creation. Auto-debit authorization. Webhook confirmation

payment.mandate.created

~1s

🏦

Distribution

MFU Central API call: SIP registration with CAN, fund ISIN, mandate reference. ISO-20022 message

sip.order.placed

~3s (MFU)

💼

Portfolio

Update Holdings

CQRS write: create pending SIP entry. Read model projection updates dashboard. XIRR recalculation scheduled

portfolio.sip.registered

~1s

🔔

Notifications

Confirm to User

Push notification + in-app MIA message: "SIP registered successfully." Email confirmation with SIP details

notification.sent

~0.5s

Compensation Path (Saga Rollback)

Notifications

Send Failure Alert

Push + MIA message: "SIP could not be completed. Tap to retry."

notification.failure.sent

Payments

Void Mandate

Cancel Razorpay mandate if not yet executed. Refund if charged.

payment.mandate.voided

Distribution

Cancel MFU Order

Send cancellation to MFU Central. Idempotent — safe if order never reached MFU.

sip.order.cancelled

Portfolio

Revert Pending

Remove pending SIP entry from write model. Trigger read model re-projection.

portfolio.sip.reverted

Software Craftsman's Note

Saga Pattern with Choreography over Orchestration. Each service publishes domain events; downstream services react independently. No central coordinator = no single point of failure. Compensation is triggered by failure events, not rollback commands.

-- Microservices Patterns, Chris Richardson (2018)

Each Kafka topic uses Avro schemas with Schema Registry. Exactly-once delivery via idempotent producers + transactional outbox pattern. All events carry CorrelationId for distributed tracing (OpenTelemetry).