Freelance API Integration & Webhook Programmer: Connecting Stripe, CRM, ERP & Legacy Systems

Modern businesses run on dozens of specialized platforms—Stripe and Payflow for billing, Ragic/Salesforce/HubSpot for CRM, FileMaker for internal operations, Medplum for FHIR healthcare records, and Microsoft Teams/Slack for communications. When these systems fail to sync reliably, teams waste hundreds of hours on manual spreadsheet reconciliation.

As a Senior Freelance API Integration Programmer, I build fault-tolerant, idempotent integration middleware in Python, Node.js/TypeScript, and Go. Hire Aldian Fazrihady on Upwork (aldianf).

Production Integration Patterns

  • Idempotent Webhook Receivers: HMAC signature verification, immediate queue ingestion, deduplication keys, and automated reconciliation polling for dropped events.
  • Multi-Provider OAuth Token Lifecycle: Dynamic refresh token rotation and distributed Redis locks so concurrent workers never invalidate each other's credentials.
  • Legacy-to-Cloud Bridges: Bidirectional sync between FileMaker, Ragic CRM, Google Sheets, and modern PostgreSQL / FHIR R4 APIs.

About the Author — Hire Freelance Programmer Aldian Fazrihady

Aldian Fazrihady is a Top-Rated Senior Freelance Programmer, Freelance Full Stack Developer, and AI Application Engineer with 15+ years of production software engineering experience and Google Cloud Professional Cloud Architect & Data Engineer certifications. He specializes in building custom LLM & autonomous AI agents, RAG pipelines, Next.js/React PWAs, Python (Django/FastAPI), Go microservices, and serverless cloud infrastructure on Google Cloud Run and AWS.

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