%% Salesforce event-driven reference architecture
%% Reference architecture: a reusable pattern, not a live client integration
flowchart TB
  subgraph z0["Your Salesforce org"]
    crm["Salesforce records<br/>selected objects"]
    flow["Flow and Apex<br/>business logic"]
    d360["Data 360<br/>data actions"]
    cdc["Change Data Capture<br/>change events"]
    pe["Platform events<br/>custom event types"]
    apexsub["Apex trigger subscribers<br/>in-org"]
  end
  subgraph z1["Your integration estate"]
    mw["Middleware<br/>MuleSoft or other"]
    bus["External event bus<br/>your cloud or streaming platform"]
    erp["ERP and back office<br/>consumers"]
    dw["Data warehouse<br/>analytics consumer"]
    dlq["Dead-letter queue<br/>failed messages"]
    mon["Monitoring<br/>alerts and dashboards"]
  end
  pubsub["Pub/Sub API<br/>gRPC, HTTP/2, Avro"]
  relay["Event relay<br/>managed relay"]
  crm -->|"record changes"| cdc
  flow -->|"publish"| pe
  d360 -.->|"data actions"| pe
  cdc -->|"subscribe"| pubsub
  pe -->|"subscribe"| pubsub
  pe -->|"in-org handling"| apexsub
  pe -->|"relayed events"| relay
  pubsub -->|"event stream"| mw
  relay -->|"relayed events"| bus
  mw -->|"normalised events"| bus
  bus -->|"business events"| erp
  bus -->|"event history"| dw
  mw -->|"failed after retries"| dlq
  dlq -->|"depth alerts"| mon
  erp -.->|"status write-back"| crm
  classDef salesforce stroke:#125BD8,fill:#e8f0fd
  class crm,flow,cdc,pe,apexsub salesforce
  classDef data stroke:#2f8a3a,fill:#e9f6ea
  class d360,dw data
  classDef integration stroke:#334155,fill:#eef2f6
  class pubsub,relay,mw integration
  classDef security stroke:#1f2937,fill:#f3f4f6
  class dlq security
  classDef external stroke:#64748b,fill:#ffffff
  class bus,erp external
  classDef people stroke:#125BD8,fill:#ffffff
  class mon people