AI, API & eCommerce Integration Services

Harper Agency specializes in the architecture, integration, and delivery of complex operational systems. We work with growing businesses and enterprise teams who need systems built right — scalable, secure, and production-ready from day one.

We are not generalists. Our work spans AI workflow integration, eCommerce architecture, marketplace synchronization, payment processing, logistics APIs, healthcare platforms, and cloud infrastructure. If the problem is complex and the stakes are high, that is where we do our best work.

15+ years of building and delivering enterprise systems — 60+ payment and fulfillment integrations deployed across thousands of merchants globally.

AI & Agentic Workflow Integrations

We integrate AI and large language models into your existing business processes — not as experiments, but as production systems. Support automation, semantic product search, intelligent inventory management, RAG-based knowledge systems, OCR pipelines, and operational copilots.

eCommerce Platform Architecture

Deep expertise across Magento/Adobe Commerce, WooCommerce, Shopify, BigCommerce, and PrestaShop. Multi-store deployments, custom checkout flows, performance optimization, and platform migrations. We have architected platforms supporting thousands of merchants and designed systems that held up under Black Friday traffic.

Marketplace Integrations

Amazon SP-API, TikTok Shop, Walmart Marketplace, eBay — inventory synchronization, product feed automation, order routing, and reconciliation systems. We build integrations that handle real-world edge cases, not just happy paths.

Payment Systems & Architecture

60+ payment and fulfillment integrations delivered across Stripe, Cybersource, Authorize.net, Moneris, Paysafe, Bambora, and Visa Direct. Full payment lifecycle design: authorization, capture, refunds, chargebacks, and reconciliation. PCI DSS compliant architecture.

Shipping & Logistics APIs

UPS, FedEx, USPS, Amazon Logistics, Canada Post, Purolator, Canpar, Loomis, ShipStation, and 3PL integrations. Real-time rate retrieval, label generation, shipment tracking, and fulfillment orchestration for Magento, WooCommerce, Shopify, BigCommerce, and PrestaShop.

Healthcare & Regulated Platforms

We have architected a WebRTC-based EMR platform serving 3,000+ patients per month — HIPAA and PIPEDA compliant, with role-based access control, full audit logging, multi-provider white-label deployment, and care plan workflows. Compliance is architecture, not a checkbox.

Systems Architecture & Cloud Infrastructure

Domain-driven design, microservices, event-driven architecture, and volatility-based decomposition. Cloud-native deployments on AWS, GCP, and Azure. API governance, observability, and operational readiness for systems that have to work when it matters. We have redesigned AWS infrastructure to survive Black Friday and architected multi-tenant SaaS platforms from the ground up.

SaaS Platform Development

Multi-tenant SaaS architecture, subscription billing with Stripe, webhook-driven systems, and white-label deployments. We have taken platforms from concept through production and through significant scaling events. If you are building a SaaS product and need the architecture designed correctly from the start, that is a conversation worth having early.