Bounded Contexts

Overview

Chakra Commerce is divided into four bounded contexts. Within each context, the model is consistent and the ubiquitous language applies without qualification. Across context boundaries, integration happens through versioned events and APIs — never through shared databases or direct object references.

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Context Map

graph TD
    subgraph orders_ctx ["Orders Context (core)"]
        ORD[Order Aggregate\nOrderPlaced · OrderConfirmed · OrderCancelled]
    end

    subgraph inventory_ctx ["Inventory Context (supporting)"]
        INV[StockItem Aggregate\nStockReserved · StockReleased]
    end

    subgraph customers_ctx ["Customers Context (supporting)"]
        CUS[Customer Aggregate\nCustomerRegistered · CustomerSuspended]
    end

    subgraph payment_ctx ["Payment Context (external)"]
        PAY[Payment Gateway\nExternal system — Stripe/Adyen]
    end

    subgraph fulfillment_ctx ["Fulfillment Context (gateway)"]
        FUL[Fulfillment Gateway\nLeave-and-Layer proxy → WMS]
        WMS[Warehouse Management System\nLegacy on-prem — untouched]
    end

    ORD -->|"PlaceOrder saga: ReserveStock command\n(Orders → Inventory)"| INV
    INV -->|"StockReserved event\n(Inventory → Orders)"| ORD
    ORD -->|"Capture payment\n(via ACL)"| PAY
    PAY -->|"PaymentCaptured / PaymentFailed\n(via ACL)"| ORD
    CUS -->|"CustomerRegistered event\n(Customers → Orders read cache)"| ORD
    CUS -->|"CustomerSuspended event\n(Customers → Orders)"| ORD
    ORD -->|"OrderConfirmed event\n(choreography — Orders does not know consumer)"| FUL
    FUL -->|"Dispatch request\n(SOAP/HTTP — translated from domain types)"| WMS

    style orders_ctx fill:#dbeafe,stroke:#3b82f6
    style inventory_ctx fill:#dcfce7,stroke:#22c55e
    style customers_ctx fill:#fef9c3,stroke:#eab308
    style payment_ctx fill:#f3f4f6,stroke:#9ca3af
    style fulfillment_ctx fill:#fce7f3,stroke:#ec4899

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Context Relationships

Relationship	Type	Description
Orders → Inventory	Partnership	Both teams coordinate on saga protocol and event schema evolution
Orders → Customers	Downstream (conformist)	Orders consumes Customer events; conforms to Customer's model
Orders → Payment	Anti-corruption layer	Payment Gateway uses external vocabulary; ACL translates to Orders model
Inventory → Orders	Upstream (open host)	Inventory publishes a stable event API; Orders is one of many consumers
Orders → Fulfillment	Choreography (published event)	Orders publishes OrderConfirmed; Fulfillment Gateway consumes independently
Fulfillment → WMS	Leave-and-layer proxy	Gateway translates domain types to legacy SOAP; WMS is untouched

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Contexts Summary

Context	Type	Core concept	Owner team	Extracted?
Orders	Core domain	Order lifecycle + saga	orders-team	Phase 4 (planned)
Inventory	Supporting	Stock reservation + CQRS	inventory-team	Phase 3 (in progress)
Customers	Supporting	Customer registration	customers-team	Phase 2 (done)
Payment	External	Card processing	vendor	N/A
Fulfillment	Gateway (leave-and-layer)	WMS proxy; async dispatch	platform-team	Deployed (permanent until WMS replaced)

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Integration Patterns Used

Published Language (Events): Domain events defined in contracts/event-schemas/ are the primary integration mechanism. Consumers read from Kafka topics and maintain local projections.

Anti-Corruption Layer (Payment): The Orders service wraps the Payment Gateway API with a PaymentGatewayAdapter that translates external types (ChargeResult, RefundResult) into Orders domain types (PaymentCaptured, PaymentFailed).

Open Host Service (Inventory API): The Inventory service exposes a stable REST API for stock reservation commands. Multiple consumers (Orders, future warehouse system) can use it without knowing Inventory internals.

Leave-and-Layer (Fulfillment Gateway): The legacy Warehouse Management System is left exactly as-is. The Fulfillment Gateway is a new service that layers a modern async interface on top — subscribing to OrderConfirmed events on Kafka and translating them into WMS SOAP calls. The WMS vendor contract, deployment, and protocol are untouched. See ADR-0011 and the contrast with Strangler Fig in ADR-0003.