API Integration for Enterprise: A Practical Guide for Canadian Companies
API integration guide for Canadian enterprise. REST vs GraphQL, OAuth 2.0 security, rate limiting, and monitoring. Built by developers who ship production systems.
What Is the Best Approach to Enterprise API Integration?
Start with a clear integration architecture before writing any code. Map your data flows, identify which systems are sources of truth, choose REST for simple CRUD operations and GraphQL for complex data queries, implement OAuth 2.0 for authentication, and build monitoring from day one. Canadian enterprises that skip the architecture step spend 3-5x more on rework. The median enterprise uses 130+ SaaS applications (Productiv, 2024) — each one a potential integration point.
If your systems do not talk to each other, your team manually bridges the gaps. Talk to our integration engineers.
REST vs GraphQL: When to Use Each
Use REST when:
- Simple CRUD operations (create, read, update, delete)
- The API serves multiple external consumers
- Caching is critical (REST caches naturally via HTTP)
- Your team is familiar with REST patterns
Use GraphQL when:
- Clients need flexible queries (mobile vs web need different data shapes)
- You want to reduce over-fetching (mobile apps on limited bandwidth)
- Multiple related entities must be fetched in a single request
- Your data model is graph-like (interconnected entities)
Most Ontario enterprise integrations use REST. GraphQL adds value for customer-facing applications with complex data requirements.
Security: OAuth 2.0 + API Keys
Every API integration must implement:
- OAuth 2.0 for user-context authentication (access tokens, refresh tokens, scopes)
- API keys for server-to-server communication (rotated quarterly minimum)
- Rate limiting to prevent abuse (start with 100 requests/minute, adjust based on usage)
- Input validation on every endpoint (never trust incoming data)
- Encryption in transit (TLS 1.3) and at rest (AES-256)
For Canadian government integrations, add Protected B compliance requirements and PIPEDA data handling obligations.
Monitoring and Observability
Build monitoring before you need it:
- Latency tracking: P50, P95, P99 response times per endpoint
- Error rates: 4xx (client errors) and 5xx (server errors) by endpoint
- Throughput: Requests per second, daily/weekly trends
- Data integrity: Reconciliation checks between source and target systems
- Alerting: PagerDuty or equivalent for > 1% error rate or > 2s P95 latency
Frequently Asked Questions
How long does a typical enterprise API integration take?
Simple integrations (connecting two SaaS tools via REST): 2-4 weeks. Complex integrations (connecting legacy ERP to multiple modern systems with data transformation): 8-16 weeks. The scoping phase (1-2 weeks) prevents scope creep.
What is the cost of a poorly integrated enterprise?
McKinsey estimates that employees spend 20% of their work week searching for information across disconnected systems. For a 200-person Ontario company at an average salary of $75,000, that is $3M/year in lost productivity.
Should I use middleware or direct API connections?
Use middleware (MuleSoft, Boomi, or custom) when you have 10+ integrations. Direct point-to-point connections work for 2-5 integrations but create a maintenance nightmare at scale. Every new system requires N-1 new connections instead of one connection to the middleware layer.
Droz Technologies builds enterprise API integrations for Ontario companies. Talk to an engineer about connecting your systems.
