Nicholas Henry Freke

Senior IBM zSeries / z/OS Systems Specialist with 25+ years' experience supporting and modernising enterprise mainframe and hybrid infrastructures within banking, financial services, and large‑scale enterprise environments. Expert in z/OS, z/VM, zLinux, WebSphere, and extensive ISV ecosystems. Proven background in system upgrades, performance tuning, automation, security integration, and 24/7 production support, combined with a strong track record of mentoring junior engineers and advising stakeholders.

Recognised for deep technical authority, operational resilience, and calm leadership in live production environments.

IBM zSeries Specialist - NTT Data Group - London

(2020-06)

• Lead installation and maintenance of z/OS service levels and fix packs across enterprise environments.
• Manage ISV upgrades (Broadcom, BMC, Sterling, Connect:Direct), ensuring platform stability and audit compliance.
• Act as senior escalation point for complex system and performance issues.
• Mentor and train junior engineers, improving team capability and operational resilience.
• Support 24/7 production systems with a focus on availability, risk reduction, and change governance.

IBM zSeries Specialist - Computacenter UK - Nottingham

(2019-06 - 2020-05)

• Delivered z/OS, DB2, Oracle, and ISV service upgrades within regulated enterprise environments.
• Provided round‑the‑clock production support, incident resolution, and root‑cause analysis.
• Collaborated with customer change management and release teams to ensure zero‑downtime deployments.

IBM WebSphere Administrator - Royal Bank of Scotland - Edinburgh

(2019-03 - 2019-05)

• Installed and configured WebSphere Application Server within secure banking infrastructure.
• Supported middleware integration with existing MQ and database services.

Career Break – Sailing with Family (Europe) - Sabbatical

(2017-05 - 2019-02)

Sabbatical demonstrating planning, responsibility, and adaptability.

IBM WebSphere Commerce / Linux Infrastructure Specialist - Nexinto GmbH (formerly EasyNet GmbH) - Hamburg

(2011-11 - 2017-04)

Contractor

• Led installation, upgrades, and operational support of WebSphere Commerce, WAS, DB2, Oracle, and Java platforms.
• Delivered Linux infrastructure automation using Puppet, Jenkins, Git, and Eclipse.
• Authored and maintained deployment and configuration scripts covering SSL, MQ/IIB, JVM tuning, Apache, MongoDB, and monitoring tools.
• Monitored application and platform health using AppDynamics and native Linux tooling.
• Managed production change requests and maintained detailed technical documentation.

zSeries WebSphere Specialist - CitiBank - Lewisham

(2010-01 - 2011-06)

Contractor

• Installed, migrated, and supported WebSphere WAS ND v7 on z/OS.
• Automated administration using JACL/Jython scripting and SMP/E.
• Integrated MQ, DB2, RACF, SSL keyrings, SOAP services, and JDBC connections.
• Performed performance tuning and JVM optimization based on GC and SMF/RMF data.
• Provided 24/7 production support in a global banking environment.