"We need to integrate with Salesforce." "Can it talk to QuickBooks?" "How does it connect to our shipping system?"
APIs are how modern software talks to other software. Here's what you need to understand.
What's an API?
API stands for Application Programming Interface. In plain English: it's a way for one piece of software to communicate with another.
Think of it like a waiter at a restaurant. You (one system) tell the waiter (API) what you want. The waiter communicates with the kitchen (another system) and brings back your food (data).
Why APIs Matter
Without APIs, your software exists in isolation. With APIs:
- Your e-commerce site can process payments (Stripe, PayPal)
- Your app can send emails (SendGrid, Mailchimp)
- Your internal tool can pull customer data (Salesforce, HubSpot)
- Your scheduling system can sync with calendars (Google, Outlook)
- Your reports can pull financial data (QuickBooks, Xero)
Modern business runs on integrated systems. APIs are the glue.
Types of Integration
One-Way Sync
Data flows in one direction.
Example: When someone submits a form on your website, their info goes into your CRM.
Pros: Simple, reliable Cons: Data only flows one way
Two-Way Sync
Data flows both directions and stays in sync.
Example: Contact changes in your CRM appear in your marketing tool, and vice versa.
Pros: Both systems stay updated Cons: More complex, potential for conflicts
Real-Time Integration
Changes happen instantly.
Example: Payment processes immediately when customer checks out.
Pros: Immediate action Cons: Requires both systems to be available
Batch Integration
Changes happen on a schedule.
Example: Sales data syncs to accounting every night at midnight.
Pros: Simpler, handles large volumes Cons: Data isn't immediately current
Common Integration Scenarios
CRM Integration
Connect your custom software to Salesforce, HubSpot, etc.
Why: Single source of truth for customer data Watch out for: Data mapping (fields don't always match perfectly)
Payment Integration
Connect to Stripe, Square, PayPal, etc.
Why: Accept payments without building payment infrastructure Watch out for: Security requirements (PCI compliance)
Email/Marketing Integration
Connect to Mailchimp, SendGrid, etc.
Why: Automated communications based on system events Watch out for: Deliverability, unsubscribe handling
Accounting Integration
Connect to QuickBooks, Xero, etc.
Why: Automated invoice creation, financial reporting Watch out for: Chart of accounts mapping, tax handling
Calendar Integration
Connect to Google Calendar, Outlook, etc.
Why: Scheduling that respects existing commitments Watch out for: Time zones, recurring events
Integration Costs
Integration work varies widely in complexity:
Simple integration: $2,000 - $5,000
- Connect to a well-documented API
- One-way data flow
- Limited data mapping
Medium integration: $5,000 - $15,000
- Two-way sync
- Multiple data types
- Error handling and retry logic
Complex integration: $15,000 - $50,000+
- Legacy systems without good APIs
- Real-time requirements
- Multiple integrations working together
- Custom middleware
Factors that increase cost:
- Poor API documentation
- Legacy systems
- High reliability requirements
- Complex business logic
- Security/compliance needs
Questions to Ask
When evaluating integration needs:
- "Does [system] have an API?" (Check their docs or ask their support)
- "Is the API well-documented?" (Good docs = easier = cheaper)
- "What data needs to flow?" (Be specific)
- "In which direction?" (One-way or two-way)
- "How current does data need to be?" (Real-time or batch)
- "What happens if the integration fails?" (Error handling)
When evaluating development partners:
- "Have you integrated with [specific system] before?"
- "Can you show me examples?"
- "How do you handle API changes?" (APIs evolve)
- "What monitoring will be in place?" (Know when things break)
Red Flags
🚩 "We can integrate with anything" without asking questions 🚩 No mention of error handling or monitoring 🚩 Assuming integrations are simple before reviewing the API 🚩 No experience with the specific systems involved
Planning for Integration
Before Building
- Identify all systems that need to connect
- Verify APIs exist and are accessible
- Get API documentation reviewed by developers
- Understand authentication requirements
- Plan for API rate limits
During Building
- Build integrations incrementally (test early)
- Create robust error handling
- Log everything for troubleshooting
- Plan for API changes
After Launch
- Monitor integration health
- Plan for API version updates
- Have fallback procedures when integrations fail
The Bottom Line
Integrations are often where projects get complicated. Good planning upfront saves significant pain later.
The question isn't "can we integrate?" — almost anything can connect to anything with enough work. The questions are:
- How much work?
- What are the failure modes?
- How will we maintain it?
A good development partner asks these questions before committing to estimates.
Need systems that talk to each other? Let's plan your integrations properly