API & Payment Integration

API Integration & Payment Gateway Integration

Payment gateways, WhatsApp, SMS, shipping and third-party APIs connected securely. Delivered by a freelance tech lead with 14+ years of experience.

Modern businesses run on many tools — payment gateways, shipping partners, SMS and WhatsApp, accounting software, marketplaces. API integration makes them talk to each other so data flows automatically instead of being copied by hand.

Every integration is built with proper error handling, logging and security, so payments, orders and notifications are reliable even at scale.

What's included

Payment gateways

Razorpay, PayU, Cashfree, Stripe, PayPal and UPI with webhooks and reconciliation.

WhatsApp & SMS

Order updates, OTPs and alerts via WhatsApp Business API and bulk SMS gateways.

Shipping & logistics

Shiprocket and courier APIs for rates, labels and live tracking.

Accounting & ERP

Sync invoices and payments with accounting and ERP software.

Custom REST APIs

Secure APIs for your mobile app, partners or internal tools.

Webhooks & automation

Event-driven workflows between your website, CRM and SaaS tools.

How we'll work together

  1. Discovery — understand your business, users and goals.
  2. Plan & quote — scope, architecture, timeline and a fixed, transparent price.
  3. Design & build — milestone-based development with regular demos.
  4. Launch & support — testing, go-live, training and ongoing optimisation.

Frequently asked questions

Can you integrate a payment gateway into my existing website?

Yes — gateways can be added to custom PHP, WordPress/WooCommerce or React-based websites with full webhook handling.

Do you build APIs for mobile apps?

Yes. Secure, documented REST APIs are built for mobile apps and third-party partners.

Have an idea?

Let's build something people remember.

Tell me what you need — website, store, CRM, app or automation. You'll get a clear plan, timeline and quote within 24 hours.