Job Title: FIS IST Switch Expert
Location: London
Employment Type: Contract
We are seeking an experienced FIS IST Switch Expert to lead the architecture, implementation, optimization, and support of the FIS International Switching (IST) platform. The ideal candidate will play a critical role in ensuring high availability, scalability, regulatory compliance, and seamless transaction processing across ATM, POS, and digital payment ecosystems.
This role requires deep expertise in payment switching, enterprise architecture, transaction routing, and modernization of legacy payment infrastructures into API-driven and cloud-enabled environments.
Define target-state architecture for FIS IST across ATM, POS, and digital payment channels.
Establish high availability, active-active, and disaster recovery designs.
Lead architecture blueprints covering transaction routing, authorization, clearing, and settlement flows.
Drive alignment with enterprise architecture standards (cloud, API, microservices).
Architect and lead migration from legacy switches (e.g., Connex, BASE24, Postilion) to IST.
Define coexistence strategies, data migration approaches, and phased cutover models.
Identify optimization opportunities to reduce latency, increase throughput, and improve resilience.
Design integration patterns with Core banking and authorization systems, Card schemes (Visa, Mastercard, domestic networks), Fraud, AML, and risk systems.
Enable transition from ISO 8583 to API/REST-based architectures.
10+ years in payment switching with deep expertise in FIS IST platform.
Proven experience in enterprise-scale switch architecture and transformation programs.
Strong command over ISO 8583, transaction lifecycle, and routing logic.
Expertise in:
Distributed systems and microservices architecture
API-first and event-driven designs
Hybrid/cloud infrastructure models
Strong understanding of HSMs, cryptography, and secure transaction processing.
Domain Expertise on Card payment ecosystems (ATM, POS, e-commerce), Scheme connectivity and certification processes, ATM operations, reconciliation, dispute management.
This position is exclusively managed by Sperton, a global talent partner connecting high-performing professionals with leading organizations worldwide.
SPERTON is a full-range provider of Global Recruitment, People Management, Global Mobility and Business support services within focused industry sectors. Our head office is located in Norway. We have over 20 years’ of experience supporting clients within the Human Resources area. We can support you globally through our own companies and partners in more than 140 countries.
Sperton had been specializing in the supply of the very best freelance and permanent white-collar professionals working with projects. We provide consultant and recruitment services to companies of all types and sizes, including consultancies, contractors, sub-contractors, developers and end clients operating across a wide range of projects and environments.
Now our services also include People Management, Global Mobility and Business Support Services.
Legal entity set-up, payroll services, HR administration, compliance, and insurance provision, cultural awareness training, and mobility support – everything needed to work compliantly with local legislation and regulations in different countries.
With over 20 years of global experience within project execution, we understand your challenges and know how to support you from the start to the end of the project.
