Integrations: where ecommerce ops quietly breaks

Your Shopify store does not exist in isolation. It connects to your warehouse, your accounting software, your email platform, your returns provider and a dozen other systems. Each connection is a potential point of failure and most brands do not know when something breaks until a customer complains.

The Integration Landscape

A typical ecommerce brand at £3m+ turnover has 8-15 system integrations. The most common:

• ERP/Accounting: Xero, QuickBooks, Sage
• Warehouse/3PL: ShipBob, Huboo, in-house WMS
• Email/CRM: Klaviyo, Mailchimp, HubSpot
• Returns: Loop, ReturnGo, manual processes
• Reviews: Yotpo, Judge.me, Trustpilot
• Analytics: GA4, Shopify Analytics, custom dashboards

Each of these connections has its own sync frequency, error handling and failure modes.

Common Failure Patterns

These are the integration failures we see most frequently:

Stock sync lag: Your 3PL updates stock levels every 15 minutes. In those 15 minutes, you can oversell popular items. The customer gets an email saying their order is delayed. Trust erodes.

Order data mismatch: Discount codes, gift cards and multi-currency orders often transmit incorrectly to accounting systems. Your finance team spends hours reconciling.

Customer data silos: Your Klaviyo segments do not match your Shopify customer tags because the sync is one-directional or delayed. Customers get irrelevant emails.

Webhook failures: Shopify sends a webhook, the receiving system is temporarily down and the event is lost. No retry. No alert. The order just... does not appear in your WMS.

Building Resilient Integrations

The principles of reliable integration:

• Idempotent operations: Every sync operation should be safe to run multiple times without creating duplicates
• Error alerting: Every integration should have monitoring that alerts on failure, not just logs it
• Retry logic: Failed API calls should retry with exponential backoff, not fail silently
• Reconciliation jobs: Daily or weekly jobs that compare data between systems and flag discrepancies

The Middleware Question

Should you use a middleware platform like Celigo, Make, or custom code?

Use middleware when: You have many simple integrations, your team is non-technical and you need quick setup.

Use custom code when: You have complex business logic, high volume, or need real-time sync.

Avoid: Point-to-point integrations between every system. This creates a web of dependencies that becomes unmaintainable.

Monitoring Your Integrations

Set up a simple dashboard that answers these questions daily:

• How many orders were synced to the WMS in the last 24 hours? Does this match Shopify?
• How many products have a stock discrepancy between Shopify and the warehouse?
• When was the last successful sync for each integration?
• Are there any failed webhooks in the retry queue?