Tandem Developer

Posted 1 day 7 hours ago by Hydrogen Group

£400 - £450 Daily
Contract
Not Specified
Other
London, United Kingdom
Job Description

Tandem Developer (Contract) - Cards & Banking

Location: London (2-3 days onsite)
Contract Duration: Until 31 December 2026
Engagement: PAYE via Umbrella only
Security: BPSS eligibility required

Role Overview

We are seeking an experienced Tandem Developer to join a technology team delivering mission-critical banking and card payment solutions. This role focuses on the Cards domain, working within a high-availability environment supporting large-scale transaction processing systems.

You will be responsible for developing, enhancing, and supporting HP NonStop (Tandem) applications that underpin card authorization, settlement, and payment processing platforms.

Key Responsibilities

  • Design, develop, and maintain applications on the HP NonStop (Tandem) platform

  • Develop and support solutions using TACL, Cobol, C, and Guardian

  • Deliver and enhance card transaction processing, authorization, and settlement systems

  • Integrate with core banking platforms, payment gateways, and downstream systems

  • Perform system analysis, troubleshooting, and performance tuning in high-volume environments

  • Ensure compliance with PCI DSS, security, and regulatory standards

  • Provide L2/L3 production support for critical card and banking applications

  • Collaborate with business analysts, engineers, and stakeholders to deliver scalable solutions


Required Skills & Experience

  • Strong hands-on experience with HP NonStop (Tandem) systems

  • Proficiency in TACL, Cobol, C, Guardian, and Enscribe/NonStop SQL

  • Solid understanding of ISO 8583 messaging and online/batch transaction processing

  • Proven experience in the Cards domain (credit/debit card processing, EMV, tokenization)

  • Experience with Base24 or similar card payment platforms

  • Strong analytical, troubleshooting, and problem-solving skills

  • Experience working with high-availability, fault-tolerant systems


Desirable Experience

  • Modernisation or transformation of Legacy Tandem applications

  • Exposure to Visa/Mastercard schemes, fraud prevention, and settlement processes

  • Banking or payments-focused certifications or formal training