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Software Delivery

API Development & Integration

Robust REST and GraphQL APIs that connect your systems, power your applications, and enable partner ecosystems. We design, build, and document APIs that developers love.

  • REST API Design
  • GraphQL
  • Third-Party Integrations
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API Development & Integration service
Key Features

What this service covers

Use development when this is the bottleneck slowing the work down.

REST API Design

Clean, versioned REST APIs following OpenAPI 3.1 standards with consistent error handling, pagination, and filtering patterns.

GraphQL

Flexible, type-safe GraphQL APIs that let clients request exactly the data they need. Subscriptions for real-time updates included.

Third-Party Integrations

Connect to Stripe, Salesforce, HubSpot, Twilio, and hundreds of other services with reliable error handling and retry logic.

Webhook Systems

Event-driven webhook delivery with signature verification, retry queues, and delivery logs for reliable system-to-system communication.

API Documentation

Interactive API docs with Swagger UI or Redoc, SDKs, code samples, and Postman collections that make integration effortless.

Rate Limiting & Security

API key management, OAuth 2.0, rate limiting, request validation, and audit logging to protect your endpoints.

APIs are the backbone of modern software. Whether you’re exposing functionality to partners, connecting internal systems, or powering a mobile app, well-designed APIs determine how effectively your software ecosystem operates.

API Design & Development

REST APIs

We build RESTful APIs that follow industry best practices:

  • Resource-oriented URL design with consistent naming conventions
  • Proper HTTP method usage (GET, POST, PUT, PATCH, DELETE)
  • Standardized error responses with meaningful error codes
  • Cursor-based and offset pagination for large datasets
  • Filtering, sorting, and field selection for flexible querying
  • HATEOAS links for discoverability

GraphQL APIs

For applications requiring flexible data fetching:

  • Schema-first design with strong type definitions
  • Query complexity analysis to prevent abuse
  • DataLoader patterns for efficient N+1 query resolution
  • Real-time subscriptions over WebSocket
  • Persisted queries for production performance
  • Federation for microservice architectures

Integration Services

Payment & Commerce

  • Stripe Connect for marketplace payments
  • PayPal, Square, and Adyen integration
  • Subscription billing and invoicing APIs
  • Tax calculation with Avalara or TaxJar

CRM & Marketing

  • Salesforce, HubSpot, and Pipedrive sync
  • Mailchimp, SendGrid, and Postmark for transactional email
  • Segment for customer data platform routing
  • Custom webhook handlers for marketing automation

Communication

  • Twilio for SMS, voice, and video
  • Slack and Microsoft Teams bot integration
  • Intercom and Zendesk for customer support
  • Push notification services (FCM, APNs)

Cloud & Infrastructure

  • AWS services (S3, SQS, Lambda, DynamoDB)
  • Google Cloud (BigQuery, Pub/Sub, Cloud Functions)
  • Azure (Blob Storage, Service Bus, Functions)
  • Cloudflare Workers for edge compute

API Security

Security is built into every API we develop:

  • OAuth 2.0 / OIDC — Industry-standard authorization flows
  • API key management — Scoped keys with rotation policies
  • Input validation — Schema-based request validation with Zod or Joi
  • Rate limiting — Sliding window algorithms with per-key and per-IP limits
  • Audit logging — Comprehensive request logging for compliance and debugging
  • CORS policies — Properly configured cross-origin resource sharing

Why Choose R5 Industries

  • Developer experience — We build APIs that external developers can integrate in minutes, not days
  • Battle-tested patterns — Retry logic, circuit breakers, and idempotency keys for production reliability
  • Comprehensive documentation — Auto-generated OpenAPI specs, interactive docs, and client SDKs
  • Monitoring included — Request tracing, latency dashboards, and error alerting from day one

Need systems that connect cleanly? Book a planning session and we will scope the API work.

Need help with api development & integration?

Start with one conversation. If the work also touches another hub, we will coordinate it from the same plan.

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