API Integration

Professional API Integration Services
Seamless, Secure & Scalable

We provide custom API integration services to connect your website, web application, or mobile app with payment gateways, CRM systems, ERP software, shipping providers, cloud platforms, and third-party services. Every integration is secure, reliable, scalable, and optimized for seamless data exchange and business automation.

Payment GatewaysCRM & SaaS SyncWebhooks & AutomationLegacy & ERP Bridges
180+
Integrations Shipped
99.9%
Avg. Integration Uptime
60%
Avg. Fewer Manual Errors
6+ Yrs
Integration Experience
Our Process

How we integrate step by step

A structured process ensures nothing gets missed, from initial discovery to a fully monitored integration launch.

  1. 01 Discover

    API Audit & Requirements Mapping

    Every system that needs to talk to another mapped out, endpoints, auth methods, rate limits, and data formats, before a single integration is built.

  2. 02 Architect

    Integration Architecture & Error Handling

    Sync strategy (real-time, webhook, or scheduled batch), retry logic, and failure handling decided up front, so a dropped connection never means dropped data.

  3. 03 Build

    Integration Development & Testing

    Connections built and tested against real API responses, edge cases, and rate limits, not just the happy path shown in the docs.

  4. 04 Launch

    Launch & Monitoring

    Load testing, logging, and alerting configured so failed calls get caught immediately, not discovered a week later. Plus 30-day post-launch support.

What's Included

Every API integration service we offer

Payments, CRMs, shipping, legacy systems, or your own custom API, we cover the entire integration landscape, not just the well-documented parts.

Payment Gateway Integration

Stripe, Razorpay, PayPal, or a custom processor wired into your checkout with webhooks for refunds, disputes, and subscription events handled correctly.

  • Stripe
  • Razorpay
  • Webhooks

CRM & Marketing Tool Integration

Salesforce, HubSpot, or your CRM of choice synced with your website or app so leads, deals, and customer data never live in two disconnected places.

  • Salesforce
  • HubSpot
  • Data Sync

Shipping & Logistics API Integration

Shiprocket, FedEx, or carrier APIs connected for live rate calculation, label generation, and tracking updates pushed straight to your customers.

  • Shiprocket
  • Tracking
  • Rate Calculation

Third-Party & SaaS API Integration

Any REST, GraphQL, or SOAP API, Google, Slack, Twilio, or a niche industry tool, connected to your product without forcing you into their SDK's limitations.

  • REST
  • GraphQL
  • SOAP

Custom API Development

Well-documented REST or GraphQL APIs built for your own product, so partners, mobile apps, or internal teams can build on top of it confidently.

  • Custom APIs
  • Documentation
  • Versioning

Legacy System & ERP Integration

Connecting modern apps to older ERPs, on-premise databases, or systems with no public API, through middleware built to bridge the gap safely.

  • ERP
  • Middleware
  • Legacy Systems

Webhook & Event-Driven Automation

Real-time event handling, order placed, payment received, ticket opened, wired to trigger the right action automatically instead of a manual check.

  • Webhooks
  • Automation
  • Real-Time Events

API Monitoring & Ongoing Support

Uptime monitoring, rate limit tracking, and version-upgrade handling, so an integration that worked at launch still works a year later.

  • Monitoring
  • Rate Limits
  • Support
What You Get

Every deliverable included

  1. Production-Ready Integration Code

    Clean, documented integration code handed off through your Git provider of choice, ready for your team to extend.

  2. Error Handling & Retry Logic

    Every integration built with retries, timeouts, and fallback behavior, so a slow or failed API call never breaks the user experience.

  3. Authentication & Key Management

    API keys, OAuth tokens, and secrets configured securely with environment-based config, never hardcoded or exposed client-side.

  4. Webhook Verification & Logging

    Incoming webhooks verified against signatures and logged, so every event is traceable when something needs debugging.

  5. API Documentation

    A written reference covering every endpoint used, its purpose, and its data shape, so your team isn't guessing six months from now.

  6. 30-Day Support Window

    Post-launch support for integration bugs, edge cases, and technical questions at no extra cost.

Selected Work

Integrations we've shipped

A cross-section of payment, CRM, shipping, and legacy system integration work across retail, SaaS, and logistics.

D2C E-Commerce

Meridian Boutique Payment & Shipping Stack

Razorpay checkout and Shiprocket tracking integrated into a Shopify storefront. Checkout failures dropped 92% and support tickets about tracking fell 60%.

  • Razorpay
  • Shiprocket
  • Webhooks
B2B SaaS

LeadPro CRM Sync

Two-way sync between a custom sales dashboard and HubSpot, keeping deal stages and contact data consistent across both systems automatically.

  • HubSpot
  • Two-Way Sync
  • REST API
Retail Chain

QuickServe POS-to-ERP Bridge

Middleware connecting a modern POS system to a 12-year-old on-premise ERP with no public API. Eliminated manual end-of-day data entry entirely.

  • ERP
  • Middleware
  • Legacy Systems
Logistics & Fleet

RouteWise Carrier Rate Engine

Live rate shopping across four shipping carriers via their APIs, picking the cheapest option automatically at checkout. Cut shipping costs 14%.

  • Carrier APIs
  • Rate Shopping
  • Automation
Professional Services

Harbor Invoicing & Payments Pipeline

Stripe subscriptions connected to an internal billing dashboard with webhook-driven invoice generation. Billing errors dropped to near zero.

  • Stripe
  • Webhooks
  • Billing Automation
Ed-Tech SaaS

SkillForge Notification & Comms Layer

Twilio and SendGrid integrated for SMS and email notifications across a learning platform, with delivery tracking and retry handling built in.

  • Twilio
  • SendGrid
  • Notifications
Client Voices

What it's like to work with us

We measure success in uptime and errors avoided, not just a green checkmark on launch day. Here's what a few clients had to say.

Our checkout used to fail silently whenever Razorpay had a hiccup. Now every failure gets caught, logged, and retried before the customer even notices.
Rohan Mehta
Founder, Meridian Boutique
Bridging our old ERP to the new POS sounded impossible until they built the middleware for it. No more end-of-day spreadsheet reconciliation.
Ananya Kapoor
Operations Head, QuickServe
The CRM sync just works. Deals update in both systems instantly and nobody on the sales team has to think about it anymore.
Daniel Cruz
Sales Director, LeadPro
Transparent Pricing

Simple, honest pricing

No hidden fees, no surprises. Choose a package that fits your scope or talk to us for a custom quote.

Starter

₹ 15Konwards

Perfect for a single, well-documented integration, like one payment gateway or one CRM connection.

  • 1 API integration
  • Error handling & retry logic
  • Webhook setup (if required)
  • Unlimited revisions
  • Basic API documentation
  • Secure key & credential setup
  • 1 year free support
  • Multi-system sync
  • Custom API development
Get Started

Enterprise

Custom

For legacy system bridges, custom API development, or teams needing an embedded integration specialist on retainer.

  • Unlimited API integrations
  • Legacy / ERP middleware
  • Custom API development
  • Unlimited revisions
  • Advanced monitoring & alerting
  • Rate-limit & version management
  • Secure key & credential setup
  • 1 year free priority support
  • Dedicated integration lead
  • Monthly retainer available
Talk to Us
FAQ

Common questions

Anything else on your mind? Drop us a message at info@sitefiy.com

Any REST, GraphQL, or SOAP API with documentation, and in many cases APIs with limited or outdated docs too. This covers payment gateways, CRMs, shipping carriers, messaging tools, and internal or legacy systems.

We build retry logic, timeouts, and fallback behavior into every integration so a temporary outage doesn't break your app. For API version changes, we set up monitoring so we catch deprecations before they cause failures.

Yes. For legacy or on-premise systems without an API, we build middleware that connects to the database or file exports directly, bridging the gap safely without touching the core system.

All keys, tokens, and secrets are stored using environment-based configuration and secret managers, never hardcoded or exposed in client-side code.

Both. If your product needs its own API for partners, mobile apps, or internal tools to build against, we design and document it from scratch with proper versioning.

A single, well-documented integration (like a payment gateway) typically takes 1–3 weeks. Multi-system integrations or legacy bridges usually take 4–8 weeks depending on complexity.

Yes. Upon receipt of final payment, full IP and the complete codebase transfer to you through your own Git repository, no vendor lock-in.

We offer optional retainers for uptime monitoring, rate-limit tracking, and handling API version upgrades after launch. It's entirely opt-in, not bundled by default.
Ready to Begin

Let's connect the systems
your business depends on

Tell us which systems need to talk to each other and we'll get back within 24 hours with a tailored integration proposal, no commitment required.