Tandem Developer

Onyx-Conseil; City Of London; Hybrid; GBP 60,000 - 80,000; Full time

Job summary

A global technology consultancy is seeking an experienced Tandem Developer to join their London team, specializing in banking applications. This role involves developing and maintaining applications on HP NonStop systems, focusing on card transaction processing and integration with banking platforms. Candidates should have expertise in TACL, COBOL, and high-availability environments. Strong analytical and problem-solving skills are essential, along with domain knowledge in payment systems. The position offers a hybrid working model.

Qualifications

• Strong experience with HP NonStop (Tandem) systems.
• Proficiency in TACL, COBOL, C, Guardian, and Enscribe/NonStop SQL.
• Hands-on experience in Cards domain with credit/debit card processing.

Responsibilities

• Design, develop, and maintain applications on the HP NonStop (Tandem) platform.
• Implement solutions for card transaction processing and settlement.
• Perform system analysis, troubleshooting, and performance tuning.

Skills

HP NonStop (Tandem) systems

TACL

COBOL

C

Guardian

Enscribe/NonStop SQL

ISO 8583 messaging

Problem-solving

Analytical skills

Education

Banking certifications

Job description

INSIDE IR35 HYBRID WORKING

We are seeking an experienced Tandem Developer to join our technology team in London, specializing in Cards domain and banking applications. The ideal candidate will have deep expertise in HP NonStop (Tandem) systems and hands‑on experience in payment processing, card transaction systems, and integration with banking platforms. This role involves developing, maintaining, and optimizing mission‑critical applications in a high‑availability environment.

Key Responsibilities:

• Application Development & Maintenance:
  • Design, develop, and maintain applications on the HP NonStop (Tandem) platform.
  • Work with TACL, COBOL, C, and Guardian for application development and support.
• Cards & Banking Domain Expertise:
  • Implement solutions for card transaction processing, settlement, and authorization systems.
  • Integrate with core banking systems, payment gateways, and regulatory compliance frameworks.
• System Analysis & Optimization: Perform system analysis, troubleshooting, and performance tuning for high‑volume transaction environments.
• Compliance & Security: Ensure adherence to PCI DSS, security standards, and regulatory requirements.
• Collaboration & Governance: Work closely with business analysts and stakeholders to deliver robust, scalable solutions.
• Production Support: Provide L2/L3 support for critical banking and card systems, ensuring minimal downtime.

Required Skills & Experience:

• Technical Expertise:
  • Strong experience with HP NonStop (Tandem) systems.
  • Proficiency in TACL, COBOL, C, Guardian, and Enscribe/NonStop SQL.
  • Knowledge of ISO 8583 messaging, batch and online transaction processing.
• Domain Knowledge:
  • Hands‑on experience in Cards domain (credit/debit card processing, EMV standards, tokenization).
  • Familiarity with Base24, payment systems, and financial transaction processing.
• Other Skills:
  • Strong problem‑solving and analytical skills.
  • Experience with fault‑tolerant systems and high‑availability architectures.

Preferred Qualifications:

• Experience with modernization strategies for legacy Tandem applications.
• Exposure to Visa/Mastercard schemes, fraud prevention, and settlement processes.
• Banking certifications or domain‑specific training in cards/payments.

LA International is a HMG approved ICT Recruitment and Project Solutions Consultancy, operating globally from the largest single site in the UK as an IT Consultancy or as an Employment Business & Agency depending upon the precise nature of the work, for security cleared jobs or non‑clearance vacancies, LA International welcome applications from all sections of the community and from people with diverse experience and backgrounds.

Award Winning LA International, winner of the Recruiter Awards for Excellence, Best IT Recruitment Company, Best Public Sector Recruitment Company and overall Gold Award winner, has now secured the most prestigious business award that any business can receive, The Queens Award for Enterprise: International Trade, for the second consecutive period.