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Payment Gateway Integration

Deep API-level payment integration with secure webhook handlers, transaction management, and automated billing for custom applications and platforms.

OVERVIEW

Payment APIs Built for Reliability and Security

When you're building a custom application, SaaS platform, or marketplace, you need payment integration that goes far beyond dropping in a checkout button. You need server-side API calls, webhook handlers that verify signatures, idempotent transaction processing, and bulletproof error recovery — because when money is involved, there's zero room for error.

Gosotek builds payment integrations at the API level, handling the full transaction lifecycle from initiation to settlement. We implement secure server-to-server communication, real-time webhook processing, automated reconciliation, subscription billing with dunning, and comprehensive audit logging. Every integration is PCI-compliant and designed to handle edge cases that simpler implementations miss — expired sessions, duplicate webhooks, partial failures, and currency conversions.

  • Server-side payment API integration
  • Webhook signature verification & processing
  • Transaction logging & audit trails
  • Automated refund & dispute handling
  • Subscription & recurring billing
  • Multi-currency & multi-gateway routing
  • PCI DSS compliant architecture
  • Payment reconciliation & reporting
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WHAT'S INCLUDED

Enterprise-Grade Payment Integration

Gateway API Integration

Full server-side integration with Razorpay, Stripe, or PayPal APIs — create orders, capture payments, handle 3D Secure, and manage the complete payment lifecycle programmatically.

Webhook Handlers

Secure webhook endpoints with signature verification, idempotency handling, and retry-safe processing — ensuring every payment event is captured exactly once, even under load.

Transaction Logging

Complete audit trails for every transaction — creation, authorization, capture, settlement, and refund events logged with timestamps, amounts, and gateway response codes.

Refund Automation

Programmatic full and partial refund processing with automatic status tracking, customer notifications, and accounting system reconciliation — eliminating manual refund workflows.

Subscription Billing

Recurring payment infrastructure with plan management, trial periods, proration, upgrade/downgrade flows, dunning sequences, and automatic payment retry on failures.

Security & Compliance

PCI DSS compliant architecture with tokenized card storage, encrypted transmission, input validation, and fraud detection rules to protect every transaction.

OUR PROCESS

How We Build Payment Integrations

01

Architecture & Planning

We map your payment flows — one-time, recurring, marketplace splits — and design the integration architecture with proper error handling, idempotency, and security measures.

02

Implementation & Testing

We build the integration with comprehensive test coverage — successful payments, failures, edge cases, webhook retries, and concurrent transactions all verified in sandbox.

03

Production & Monitoring

Deploy to production with real-time monitoring of success rates, webhook delivery, and transaction volumes. We stay on call for the first week to ensure everything runs flawlessly.

WHY GOSOTEK

Why Choose Us for Payment API Integration

Zero Compromise on Security

Every payment integration follows PCI DSS guidelines with tokenization, signature verification, and encrypted communication. Security is never an afterthought.

Battle-Tested Code

Our payment code handles edge cases that others miss — duplicate webhooks, expired sessions, network timeouts, and partial failures. Production-proven reliability.

Complete Visibility

Detailed transaction logging and dashboards give you full visibility into payment flows, success rates, and revenue — making audits and troubleshooting straightforward.

Expert Support

Payment issues need immediate attention. Our team provides priority support for payment-related concerns with rapid response times and deep technical expertise.

Need Secure Payment API Integration?

Let's architect a payment system that handles your transaction volume securely and reliably. Free technical consultation to plan your integration.

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