The Integration Imperative#
Modern ERP systems do not operate in isolation. They must integrate with CRM, e-commerce, warehouse management, manufacturing execution, banking platforms, and dozens of other systems. Integration architecture determines whether these connections are assets or liabilities.
API-First Architecture#
API-first architecture designs the API as a primary interface, not an afterthought. The API is treated as a product with its own lifecycle, documentation, and governance.
REST APIs#
REST (Representational State Transfer) is the dominant pattern for ERP APIs.
Resources: Data is modelled as resources (customers, orders, invoices) with unique identifiers.
HTTP methods: Standard methods (GET, POST, PUT, DELETE) perform operations on resources.
Statelessness: Each request contains all necessary context. No server-side session state.
Standard formats: JSON is the default, with XML often supported for legacy compatibility.
Webhooks#
Webhooks provide event-driven notification. Instead of polling for changes, the ERP pushes notifications when events occur.
Use cases: Real-time synchronisation, alerting, workflow triggering.
Implementation considerations: Endpoint availability, retry logic, ordering guarantees.
GraphQL#
Some modern ERP systems offer GraphQL APIs that allow clients to request exactly the data they need.
Advantages: Reduced over-fetching, flexible queries, single endpoint.
Disadvantages: More complex server implementation, potential for expensive queries.
Integration Patterns#
Batch Synchronisation#
Data is synchronised in scheduled batches (hourly, daily).
Advantages: Simple to implement and debug. Predictable load patterns.
Disadvantages: Data is always somewhat stale. Large batches can create performance issues.
Real-Time Synchronisation#
Data is synchronised immediately as changes occur.
Advantages: Current data across all systems. Immediate visibility.
Disadvantages: Higher complexity. Greater impact from failures.
Event Sourcing#
Changes are captured as immutable events that can be replayed.
Advantages: Complete audit trail. Ability to rebuild state from events.
Disadvantages: Higher storage requirements. More complex queries.
NZ/AU Integration Considerations#
Banking Integration#
NZ: Batch payments via direct credit files. Real-time payment APIs emerging.
AU: New Payments Platform (NPP) enables real-time payments. BPAY integration for bill payments.
Government Integration#
Inland Revenue (NZ): IR Gateway services for GST, payroll filing.
ATO (AU): SBR (Standard Business Reporting) for tax and superannuation.
E-Commerce Integration#
Trade Me: API access for inventory and order management.
Afterpay/Zip: BNPL provider APIs for payment processing.
Integration Governance#
API Versioning#
APIs evolve. Versioning strategy determines how breaking changes are handled.
URL versioning: /api/v1/customers vs /api/v2/customers
Header versioning: Version specified in request header.
Rate Limiting#
APIs often have rate limits to protect system stability.
Identify limits: Understand your vendor's rate limits before designing integrations.
Plan for throttling: Implement retry logic with exponential backoff.
Error Handling#
Robust error handling is critical for production integrations.
Structured errors: APIs should return structured error responses.
Retry logic: Transient errors should be retried automatically.
Dead letter handling: Failed messages should be captured for analysis.
Monday Morning Action Plan#
This week:
- Catalogue Your Integrations: List every system that must connect to your ERP. For each, note: data flow direction, frequency needs, and criticality.
- Audit Your API Maturity: Request your vendor's API documentation. If it's thinner than this article, you have an integration problem.
- Rate Your Integration Complexity: <5 integrations = simple. 5-15 = moderate. >15 = complex. Complex scenarios need dedicated integration architecture.
- Test Real Banking Integration: For NZ/AU, verify the vendor supports direct credit files (NZ), BPAY/NPP (AU), and bank statement formats.
- Plan Your Middleware: If you have >10 integrations, you likely need an integration platform (iPaaS). Budget $50-100K for integration infrastructure.
---
Conclusion: Invest in Integration Architecture#
Integration architecture is not a technical detail. It determines whether your ERP is an integrated platform or an isolated island of data. Invest in understanding your integration requirements and designing appropriate patterns.