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Payment System Integration

We implement secure online payments, subscriptions, and billing workflows that improve conversion, reduce payment failures, and keep financial operations auditable.

What It Is

Payment integration is more than connecting a gateway API. It is a full financial flow that includes:

  • Checkout and payment method orchestration
  • Subscription and recurring billing logic
  • Webhook processing and state synchronization
  • Refunds, disputes, and reconciliation
  • Reporting and operational controls

We design end-to-end payment architecture so transactions are reliable, secure, and consistent across product, finance, and support workflows.

Business Benefits

  • Increased sales through smoother checkout flows
  • Higher conversion with trusted payment experiences
  • Better customer retention via stable subscription billing
  • Fewer failed payments and involuntary churn
  • Lower manual effort in finance and support operations
  • Better transparency for revenue and payment status

Technical Benefits

  • PCI-aware architecture and tokenization-based security
  • Idempotent API integration for safe retries
  • Webhook signature verification and delivery retry handling
  • Clear payment state machine and event-driven processing
  • Fraud mitigation controls, risk checks, and 3DS/SCA support
  • Reconciliation logic between gateway, app, and accounting data
  • Structured audit trails for compliance and incident analysis
  • Monitoring for authorization rate, decline reasons, and webhook health

Typical Integration Scenarios

  • One-time payments for digital or physical goods
  • Subscription billing with trials, upgrades, downgrades, and renewals
  • Marketplace or multi-merchant billing workflows
  • Multi-provider routing for geography, methods, and redundancy
  • Wallet and express checkout methods (Apple Pay / Google Pay)
  • Automated invoicing and refund operations

How We Work

  1. Provider selection and requirements
    Match gateway capabilities to business model, geography, currencies, and compliance needs.

  2. API integration and checkout UX
    Implement secure payment flows and optimize the checkout experience for conversion.

  3. Webhooks, refunds, and reconciliation
    Build reliable event handling, refund workflows, and finance-grade reconciliation logic.

  4. Testing, security, and go-live
    Validate edge cases, failure modes, and security controls before production launch.

  5. Monitoring and ongoing optimization
    Track payment KPIs, reduce declines, and continuously improve billing performance.

Security and Reliability Controls

  • Signed webhook verification and replay protection
  • Idempotency keys across charge and subscription operations
  • Timeout/retry policies with safe failure handling
  • Sensitive data minimization and encrypted storage
  • Fraud and risk rules with manual review paths when needed
  • Alerting for payment outages, failure spikes, and reconciliation drift

Technologies

  • Stripe
  • Fondy
  • PayPal
  • Apple Pay / Google Pay
  • 3DS / SCA
  • Subscription and billing orchestration services
  • Monitoring and reconciliation tooling

Result

  • Reliable billing and payment processing system
  • Transparent reporting and reconciliation across systems
  • Secure and scalable payment architecture
  • Improved conversion and reduced payment-related churn

Let’s Discuss Your Project

Share your business model, target markets, and billing requirements, and we will propose a payment integration plan with scope, timeline, and reliability controls.