Vertical SaaS platforms adding virtual/physical corporate cards, yield-bearing operating accounts, and instant vendor payouts directly inside their product frequently search to hire a freelance Embedded Finance & Banking-as-a-Service (Stripe Issuing, Stripe Treasury, Unit, Lithic, Marqeta, Column) programmer. I am Aldian Fazrihady, a Senior Freelance FinTech & Full Stack Programmer available via Upwork.

Core Embedded Finance & Card Issuing Capabilities

  • Sub-Second Real-Time Authorization Webhooks (JIT Funding): Responding to Stripe Issuing / Lithic / Marqeta real-time card authorization requests within the strict 1,500ms processor SLA using low-latency Go/Python handlers backed by atomic PostgreSQL/Redis spend controls.
  • Custom MCC, Velocity & Per-Employee Spend Limits: Enforcing merchant-category-code (MCC) allowlists, daily/monthly budgets, and automatic receipt-capture prompts via SMS/Slack the moment a card is swiped.
  • ACH, FedNow, RTP & Wire Reconciliation: Synchronizing BaaS settlement files with double-entry internal ledgers and automated NACHA return code (`R01`, `R03`, `R10`) state machines.

Frequently Asked Questions

How do you ensure a real-time card authorization webhook never times out at the checkout register?

I keep the hot authorization path 100% free of external third-party HTTP calls—evaluating spend rules and reserving balance inside a single indexed PostgreSQL transaction or Redis Lua script in under 30 milliseconds.

How can we hire you as a freelance Embedded Finance programmer?

Message me on Upwork.


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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