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Event flow

This section describes the path from checkout completion to downstream delivery.

Step-by-step flow

1) Customer completes checkout in Shopify.

2) Shopify emits a checkout_completed or purchase event to the App Pixel.

3) The pixel applies consent gating and derives a stable event_id (for example, using a platform-provided event id or a deterministic hash of order id and timestamp).

4) The pixel sends a normalized event to the ingest layer.

5) The ingest layer validates required fields, preserves event_id, and assigns a dedup key.

6) The event is delivered either directly (best-effort) or via a queue (durable).

7) Destinations accept the event and apply their own validation and de-duplication.

8) If a receipt is available, it is logged for verification.

Sequence diagram

sequenceDiagram
  participant C as Customer
  participant S as Shopify Checkout
  participant P as App Pixel
  participant I as Ingest
  participant Q as Queue/Relay
  participant D as Destination

  C->>S: Completes checkout
  S-->>P: Emits checkout_completed
  P->>P: Apply consent gating\nDerive event_id
  P->>I: Send normalized event
  I->>I: Validate + dedup key
  alt Durable delivery
    I->>Q: Enqueue event
    Q->>D: Deliver with retries
  else Best-effort delivery
    I->>D: Deliver immediately
  end
  D-->>I: Receipt or status (if available)

  • event_id should be stable across client and server paths to support destination-side de-duplication.

  • If consent is denied, identifiers are withheld and only non-PII event data is sent where allowed.

Canonical explainer

See https://ty-bridge.com/explainers/.