Payment systems architecture consulting

I help fintech and banking teams design, stabilize, and modernize the systems that move money. That includes payment gateways, acquiring and issuing platforms, and payment facilitator infrastructure — built to stay inside PCI-DSS scope and to keep working under real transaction volume, not just in a demo. If you're evaluating a new payment architecture, or inheriting one that's outgrown its original design, this is the work I do.

Payment systems fail in specific, well-understood ways: idempotency gaps that double-charge a customer, reconciliation drift between your ledger and the processor's, and compliance scope that quietly expands until an audit finds it. The architecture work is about closing those gaps before they reach production, not documenting them after an incident.

Engagements typically cover target-state architecture design, a modernization roadmap for legacy payment platforms, gateway and processor integration patterns, and PCI-DSS scope reduction — designing systems so cardholder data touches as few components as possible, which lowers both audit cost and breach risk. I write implementation-ready documentation, not slide decks: sequence diagrams, data flow maps, and the specific trade-offs a team needs to make a call, not just a recommendation to "modernize."

Fifteen-plus years building and scaling systems in fintech and banking, with deep, hands-on experience across the payment stack: gateway processors, payment facilitators, and acquiring and issuing systems. That includes building PCI compliant platforms from the ground up and stabilizing legacy payment systems that were processing real, high-volume transaction load under active compliance requirements — the kind of environment where a wrong migration step has a customer-facing blast radius, not just a rollback.

Client engagement details stay confidential; the pattern that repeats across them doesn't. Teams come in with a payment system that grew organically — one that worked at low volume, and started breaking (or scaring the compliance team) as volume grew. The fix is rarely a full rewrite. It's usually a target architecture, a sequenced migration plan that doesn't require downtime, and PCI scope drawn correctly from the start.