Custom API Development and Integration — I architect, develop and integrate production-quality APIs to integrate your company with payments, third-party systems, AI services and internal tools. Whether it's a straightforward REST or GraphQL API or complex event-driven integration with LMS, payments gateways or enterprise systems, each and every API I deliver is architected for robustness, security, and long-term maintenance.
Here's What Makes My API Deliverables Stand Out:
- 11+ production API systems delivered end-to-end across various industries
- Specialization in idempotence, retries and circuit breaker pattern implementation
- Signature and token rotation on all my API integrations
- Quota-aware clients with throttling on rate-limited APIs
- Exactly once processing guarantees in an event-driven inbox architecture
- Out-of-the-box observability with Datadog, Sentry and PagerDuty
- All claims proven with actual portfolio of numbers
What I Provide:
- Custom REST APIs using FastAPI, Express, and Django REST Framework
- GraphQL APIs using Apollo Server and typed resolvers
- Integrations to payment systems like Stripe, Stripe Connect, and Airwallex
- Integration to Learning Management Systems like Canvas, Panopto, and Blackboard
- Integration to communication services such as Twilio, SendGrid, and Slack
- OAuth2 authentication with automatic token refreshing and 401 error handling
- Webhook pipeline design which is idempotent to prevent duplicate charges
- Event-driven architecture implementation using inbox pattern and Celery
- Rate limit implementation with exponential backoff strategy
- Optimized cursor-based pagination for large datasets
- Complete OpenAPI specification documentation
Technical Stack:
Python, FastAPI, Django, Node.js, Express, PostgreSQL, MongoDB, Redis, Celery, Stripe, Stripe Connect, Airwallex, Canvas API, Panopto API, Twilio, OAuth2, GraphQL, REST, Docker, AWS, Datadog.
Proven Delivery Outcomes:
✅ Airwallex Payments API – 99.99% successful delivery of webhooks
✅ Canvas LMS Integration – 50K+ calls to API per day without any rate limit problems
✅ Stripe Connect Payments – automated payments splitting among parties with no disputes
✅ Panopto Automations – 3,000 lectures auto-published each term
✅ Twilio SMS Integration – magic link rescheduling functionality at scale
✅ OAuth2 Tokens Rotation – completely solved all authentication problems
No matter if it is a fresh new API from scratch, third-party integration that needs to handle rate limits and failures or broken integration that needs help to survive – I deliver reliable APIs for you.