Real-time Enrichment

💼 Business Context

• Lets downstream consumers get rich context (customer tier, product category, current cart value) without each one re-querying multiple systems
• Powers real-time use cases (in-session personalization) that can't wait for a batch join
• Owned by Platform Engineering, with enrichment sources owned by the relevant domain teams

🔌 Technical Overview

Real-time Enrichment joins each event, in-stream, against fast lookup sources: the Identity & Profile Service (customer tier, LTV band), a product catalog cache (category, price tier), and current session state (running cart value). These lookups are backed by Azure Cache for Redis to keep per-event latency low, with the underlying Data Lakehouse tables as the periodically refreshed source of truth for the cache.

💾 Enriched Event Excerpt

"enrichment": {
  "customer_tier": "gold",
  "product_category": "audio",
  "session_cart_value": 6998
}

🔗 Integration Points

• Azure Cache for Redis — low-latency lookup cache for profile/catalog/session data
• Identity & Profile Service — source of customer-tier/LTV enrichment
• Product catalog service — source of category/price enrichment
• .NET Core Stream Worker — where the joins are performed inline

🧰 Services Consumed

• Owning microservice — Cxos.Processing.Api (see the Full Application Service Map)
• Database — ADLS Gen2 (Iceberg) + Cosmos DB Table API (stream checkpoints)

⚠️ Non-Functional Considerations

• Scale: cache-backed lookups keep enrichment cost roughly constant regardless of event volume
• Latency: adds low-single-digit milliseconds per lookup; enrichment failures degrade gracefully (event proceeds with partial enrichment)
• Reliability: cache staleness is bounded by a refresh interval appropriate to each source's rate of change
• Security/Privacy: only non-sensitive, business-purpose fields are added — enrichment is scoped, not an unrestricted profile dump

🎯 Enterprise Example

A gold-tier customer adds a fourth item to their cart. Real-time enrichment attaches their tier and running cart value to the event inline, letting the Activation API trigger a tier-appropriate free-shipping nudge within the same session — a use case that would be impossible if enrichment only happened in a nightly batch job.