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UK | FIS Inter System Transaction(IST) Switch Expert

Internal
EngineeringLondon, UKHybridFull-time

About the Role

Colate is looking for a FIS Inter System Transaction(IST) Switch Expert. The FIS IST Switch Expert will be responsible for the design, implementation, optimization, and support of the FIS International Switching (IST) platform, ensuring high availability, regulatory compliance, and seamless transaction processing across ATM, POS, and digital payment channels.

Responsibilities

Key Responsibilities

  • 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

Requirements

Required Skills & Experience

 

  • 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 micro-services 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

Benefits

Please visit https://colate.io/

Skills

RequiredFIS IST platformCard payment ecosystems (ATMPOSe-commerce)
Nice to haveISO 8583ConnexBASE24Postilion

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Deadline: June 26, 2026

Department

Engineering

Location

London, UK

Work Type

Hybrid

Employment

Full-time