Custom API Development & System Integrations
Robust REST & GraphQL APIs, Payment Gateways & Seamless Enterprise Connectors
Connect your disparate business tools and automate complex workflows. FeelTech Solution builds secure, high-throughput REST and GraphQL APIs, integrating payment systems, CRMs, ERPs, shipping carriers, and marketing platforms into unified digital ecosystems.
Key Benefits & Business Advantages
Eliminate Manual Data Entry
Automatically synchronize records, orders, invoices, and customer details across all software tools in real-time.
High-Throughput & Low Latency
Architected for high concurrency, sub-50ms response times, and resilience against sudden traffic bursts.
Bank-Grade API Security
OAuth2, JWT authentication, rate limiting, IP whitelisting, and strict payload validation to prevent unauthorized access.
Comprehensive Engineering Features
Custom RESTful & GraphQL APIs
Clean, self-documenting API endpoints built according to OpenAPI / Swagger specifications.
Payment Gateway Integrations
Integration with Razorpay, Stripe, PayU, Cashfree, PayPal, and recurring subscription webhooks.
CRM & ERP Connectors
Bi-directional data sync with Salesforce, Zoho, HubSpot, SAP, and custom ERP systems.
WhatsApp & SMS Gateway APIs
Automated OTP verification, transactional notifications, and marketing broadcast triggers.
Shipping & Logistics APIs
Real-time shipping rate calculation, automatic waybill generation, and shipment tracking.
Webhook Architecture & Message Queues
Reliable event-driven webhooks with automatic retry logic and dead-letter queues.
Technologies & Frameworks We Use
Node.js & Express
Fast asynchronous API microservices
TypeScript
Type-safe schemas and validated request DTOs
Python / FastAPI
High-speed API routing & data processing
PostgreSQL & Redis
Optimized queries and cached response payloads
OpenAPI / Swagger
Interactive developer documentation
Postman & Newman
Automated regression testing suites
Our Structured Development Process
Data Contract & Schema Design
Defining endpoint paths, request payloads, response structures, and status codes.
Security & Authentication
Implementing API keys, JWT access tokens, role permissions, and rate limiters.
Business Logic & Integration
Writing performant database queries, third-party connectors, and error-handling routines.
Automated Testing & Documentation
Validating edge cases, verifying payload security, and publishing OpenAPI documentation.
Real-World Use Cases & Implementations
E-Commerce Accounting Sync
Automatically push online orders and payments into Tally or Zoho Books for instant tax filing.
Customer Mobile App Backend
Single API layer powering native iOS and Android mobile apps with shared business logic.
Third-Party Developer Platform
Monetize or expand your platform by offering public developer APIs with API key tracking.
Got Questions About Our API Development?
What is the difference between REST and GraphQL?
REST uses fixed endpoints for specific resources, making it simple and widely supported. GraphQL allows clients to request only the exact fields they need in a single query, making it ideal for complex mobile apps.
Can you connect our legacy internal software to a modern web application?
Yes. We build custom API wrappers and middleware bridges that securely expose legacy databases or internal programs to modern cloud applications.
Ready to Kickstart Your Project?
Every project includes 1 full year of free hosting management and 6 months of dedicated post-launch maintenance.