Mainframe Security Engineer - Freelance

Context

As a Mainframe Operational Security Engineer, you will be the go-to expert keeping our bank’s Mainframe environment secure, compliant, and resilient.

Missions

• Manage user permissions and access for systems outside IAM, ensuring security without blocking operations.

• Manage the content of the RACF Database, either manually or by automation.

• Create clear security documentation and standards so teams know what to do and why it matters.

• Handle encryption tasks, from importing certificates to configuring technical agents for Hardware Security Modules (HSMs).

• Assess the security of new Mainframe products, making sure they’re safe before they go live.

• Team up with Squad members to resolve security incidents, from decoding error messages to implementing fixes with minimal disruption.

• Support internal clients (IT Risk, Asset Owners, auditors) by providing evidence for compliance and addressing audit findings.

• Anticipate potential risks, and address them before they become issues for our clients.

• Participate in Squad on-call to resolve critical job failures that occur outside business hours (approximately 1 week per month covering non-business hours including weekends and holidays).

Tools & Environment

• RACF and the surrounding utilities

• Mainframe Architecture

• Basic Mainframe Tools (JCL, ISPF, REXX, SDSF, etc.)

• Role Based Security Modelling

• AT-TLS & Certificates

• Security of DB2, IMS (database and transaction management), and MQ

• Job Scheduling

• Mainframe system subsystems and their security (Spool, network, storage, SMF, etc.)

• Public Key Infrastructure & the Mainframe CryptoCards

• Unix System Service

• Preferable knowledge: zSecure product suite, job scheduler Control, COBOL, Endevor

Working Conditions

• Telework: Mandatory 50% on site & 50% homeworking

• Travel: N/A

Language Requirements

• English: Mandatory

• Dutch: Preferable

• French: Preferable

Education & Certification

• Bachelor Degree

• Mandatory certification: RACF Security Administrator

• Preferable certification: zSecure RACF

Experience

• At least 10 years of relevant experience

• Mandatory business experience: Cybersecurity experience with hands-on Mainframe expertise and the drive to build it

• Preferable business experience: Financial sector

Soft Skills

• Analytical skills: Navigate complex scenarios with conflicting security rules across different manuals

• Critical thinking: Verify requests against security standards

• Problem-solving: Trace root causes from vague error messages and fix them

• Creativity: Design custom solutions for numerous compliance points where no playbook exists

• Agile mindset: Thrive in teamwork while owning your part or eager to learn

• Proactivity: Spot risks early and resolve them before escalation in a high-volume environment