I will integrate any REST XML API with zapier klaviyo stripe and payment service

I integrate REST APIs, payment gateways, and third-party services into your existing systems. With 16 years of software engineering experience and 8 years specializing in payment infrastructure, I deliver reliable integrations that work in production, not just in testing.

What I deliver:

• REST and XML API integrations with any third-party service: Stripe, PayPal, Shopify, Klaviyo, Twilio, HubSpot, Salesforce, Xero, QuickBooks, and more
• Payment gateway setup: checkout flows, subscription billing, webhook handling, multi-currency, refund logic, and PCI-compliant architecture
• Zapier and n8n workflow connections between your tools, with proper error handling and retry logic
• Webhook receivers and event-driven architectures that process data in real time
• Authentication and security: OAuth 2.0, API key management, token refresh, rate limiting
• Data mapping and transformation between systems with different formats or schemas

How I work:

• Fixed scope, fixed price, concrete deliverable
• Clean, documented code with proper error handling and logging
• Full testing before delivery, including edge cases
• Regular communication and progress updates throughout the project
• Handover documentation so your team can maintain the integration

I have hands-on production experience with card issuing (VISA, MasterCard), PSP integrations, EMI/BaaS platforms, and prepaid card lifecycle management. Whether you need a simple Stripe checkout or a complex multi-provider payment orchestration layer, I deliver systems built to last.