Implementation Roadmap¶
This is the recommended build order if you want a practical path from zero to quick-commerce-grade architecture.
Phase 0: Foundations¶
Goal:
- establish tenant, merchant, store, item, and source identity model
Build:
- canonical schema in PostgreSQL
- source mapping tables
- object storage for raw payload archive
- Redis cluster
- Kafka / Redpanda cluster
Deliverables:
tenantsmerchantsstoressource_mappingscatalog_itemsinventory_positions
Phase 1: Catalog Ingestion MVP¶
Goal:
- ingest menu / SKU changes from one provider and serve catalog quickly
Build:
- Webhook Gateway
- one adapter, e.g. PetPooja or one ERP provider
- normalization service
- catalog read API
- Redis-backed catalog cache
Success criteria:
- item change visible in app within 5 seconds
- replay support for failed payloads
Phase 2: Real-Time Inventory¶
Goal:
- make stock and orderability trustworthy
Build:
- inventory ledger model
- stock delta processor
- reservation / release flow
- orderability rules
- inventory cache
Add rules for:
- zero stock
- blocked stock
- store closed
- menu item disabled
Success criteria:
- out-of-stock reflects in app within seconds
- no negative ATS from duplicate events
Phase 3: Dark Store and Assortment Layer¶
Goal:
- support hyperlocal commerce and store-specific availability
Build:
- store assortment table
- slotting metadata
- per-store price overrides
- substitute recommendations for unavailable items
Success criteria:
- same item can be visible in one store and hidden in another
- store-level pricing and inventory are independent
Phase 4: Search¶
Goal:
- replace catalog scans with indexed search
Build:
- search document builder
- OpenSearch index
- autocomplete
- filters by category / brand / stock / price
Search document should contain:
- item title
- normalized title
- synonyms
- brand
- category path
- store availability
- effective price
Success criteria:
- p95 search latency under 200 ms
Phase 5: Recommendation System¶
Goal:
- improve basket building and substitution
Build in order:
- rule-based complements
- popular-in-store lists
- co-purchase aggregates
- personalized ranking later
Examples:
- milk -> bread, eggs, cereal
- burger -> fries, cola
- out-of-stock item -> same-brand substitute
Phase 6: LLM Enrichment¶
Goal:
- improve data quality and searchability
Use LLMs only for asynchronous enrichment:
- title cleanup
- synonym generation
- category suggestions
- duplicate detection hints
- missing attribute completion
Do not use LLMs:
- in checkout path
- for live inventory truth
- as the sole pricing authority
Human review should still exist for high-impact changes.
Recommended Service Rollout Order¶
integration-gatewaycatalog-normalizercatalog-apiinventory-servicesearch-indexerrecommendation-serviceenrichment-service
Suggested Repo Split¶
When you move beyond docs, split repos roughly like this:
catalog-platform-corecatalog-integration-gatewayinventory-servicesearch-servicerecommendation-serviceenrichment-servicepos-uior this current frontend repo
How This Connects Back to This POS UI¶
The current frontend can evolve in stages:
Stage A¶
Replace demo product data with real catalog APIs.
Stage B¶
Replace local item stock display with inventory API.
Stage C¶
Add live inventory / store status refresh through SSE or WebSocket.
Stage D¶
Add recommendations to product grid, cart, and payment success flows.
Next Practical Build¶
If you want me to keep going from here, the best next artifact is one of:
- an OpenAPI spec for the catalog and inventory APIs
- a PostgreSQL schema for canonical catalog + inventory tables
- a Kafka topic and event-schema package
- a backend starter service for the webhook gateway
My recommendation:
- start with
2and4together - schema first, webhook service second