Principal Security Engineer

Lindar; United Kingdom; Hybrid; GBP 90,000 - 140,000; Full time

Benefits offered by this job

Health insurance

Parental leave

Birthday leave

Life insurance

Wellness incentives

Growth allowance

Flexible working

Job summary

MrQ in the United Kingdom is seeking a Principal Security Engineer to own the security engineering stack, designing zero-trust architecture and deploying EDR/XDR, SASE, SIEM, and DLP across AWS, SaaS, and endpoints. You will translate strategy into production and drive security outcomes at scale.

You’ll lead incident response, threat intelligence, vulnerability management, and audit readiness for ISO 27001, SOC 2 and GDPR, while collaborating with a multinational team in a flexible, hybrid work

Qualifications

• 6+ years in security engineering, enterprise security or security operations.
• Hands-on experience deploying, configuring, managing and troubleshooting enterprise security tools.
• Expert-level knowledge of identity and access management SSO, SAML, OAuth, SCIM, MFA, passwordless with zero trust.
• Led incident response investigations end-to-end with playbooks and remediation.
• Automation experience with Python/Bash/PowerShell for detection engineering and security ops.
• Proven ability implementing controls for ISO 27001, SOC 2, Cyber Essentials or GDPR.
• Familiarity with MITRE ATT&CK, NIST CSF, CIS Controls, OWASP.
• Experience securing cloud-native and SaaS-heavy environments (AWS).

Responsibilities

• Architect and deploy the full security tooling stack across AWS, SaaS, endpoints, network and identity.
• Build, tune and maintain detections mapped to MITRE ATT&CK with low false positives.
• Automate security operations with scripts for response, access reviews and compliance checks.
• Lead security incidents end-to-end and develop IR playbooks and runbooks.
• Own vulnerability management across infrastructure, endpoints and applications.
• Ensure technical controls and audit evidence for ISO 27001, SOC 2, Cyber Essentials and GDPR.

Skills

Security architecture

EDR/XDR deployment

SIEM & DLP

Identity & access management

Incident response

Automation scripting

Threat intelligence

Cloud security (AWS)

MITRE ATT&CK

Zero trust

Tools

CrowdStrike

SentinelOne

Netskope

Zscaler

Job description

Mr Who?

MrQ - we're an awesome, award winning online casino launched in 2018. We're big on tech, big on performance and most of all - big on fun. Over the years, we have experienced explosive growth - which means we need more rock stars to join our quest for total world domination.

MrQ runs a real-money gaming platform for 300,000+ active players - payment flows, player data, an AWS-native platform, and a company that’s deeply AI-native across the board. That’s a lot of technical surface area. Someone needs to own securing it at the engineering level: the tooling, the detection, the identity architecture, the vulnerability management, the incident response. That’s this role. You’re the hands-on technical builder of MrQ’s security engineering function - architecting and running the stack that the security strategy depends on.

You report to the Head of Security, who owns the roadmap and the board relationship. You own making that roadmap real in production.

This is a Principal role in the truest sense: deep technical ownership, accountable for delivering complex, high-impact initiatives.

What You Will Do

1. Security Architecture, Tooling & Engineering

• Security Stack: Evaluate, select, deploy, configure and manage the full enterprise security tooling suite from scratch - EDR/XDR (CrowdStrike/SentinelOne), SASE/SWG (Netskope/Zscaler), SIEM, email security, DLP, endpoint privilege management, application allowlisting.
• Architecture: Design and implement enterprise security architecture built on zero trust and secure-by-default principles. Own the technical blueprint across cloud (AWS), SaaS, endpoints, network and identity.
• Detection Engineering: Build, tune and maintain detection rules, correlation logic and alerting across SIEM and EDR. Engineer high-fidelity detections mapped to MITRE ATT&CK. Continuously reduce false positives and expand coverage.
• Automation: Engineer automation for security operations at scale - scripting (Python, Bash, PowerShell) for response orchestration, access reviews, compliance checks, vulnerability reporting, threat intel enrichment.
• Integration & Evaluation: Ensure all security tooling integrates with existing infrastructure and identity platforms. Lead POCs, vendor evaluations and build-vs-buy recommendations for new security technologies.

2. Security Operations & Incident Response

• Security incident and breach response: Run the technical response of security incidents end to end - detection, triage, supporting containment, eradication, recovery and post-incident review. Author and maintain IR playbooks, runbooks and escalation procedures. Production incidents belong to Engineering’s on-call team, but where it impacts security you are the technical security expert of the response.
• Threat Intelligence: Investigate security events, perform root cause analysis, and apply threat intelligence to improve defensive posture. Understand attacker TTPs and operationalise frameworks like MITRE ATT&CK and NIST CSF.
• Vulnerability Management: Own the vulnerability management programme end to end - scanning, prioritisation, remediation tracking, SLA enforcement and reporting to the Head of Security, across infrastructure, endpoints and applications.
• Application & API Security: Assess the security of internal applications, third‑party integrations, APIs, payment flows and authentication systems. Identify both technical vulnerabilities and product‑level abuse scenarios.

3. Identity, Access & Endpoint Security

• IAM & Zero Trust: Architect and implement identity and access controls - SSO, MFA, SAML, OAuth, SCIM, conditional access, passwordless authentication. Design and enforce least‑privilege and zero trust access policies across all systems.
• Endpoint Security: Define and enforce endpoint security standards at scale - hardening, patching, disk encryption, MDM, device compliance. Own the security posture of the macOS and Windows fleet, with IT Operations running day‑to‑day device management.
• Access Governance: Design access review and certification programmes and run them with IT Operations. Proactively identify over‑provisioned access, orphaned accounts, shadow IT and policy gaps. Maintain a clean, auditable access estate.

4. Compliance Evidence & Documentation

• Control Implementation: Implement and test the technical controls behind the security framework - ISO 27001, SOC 2, Cyber Essentials, GDPR. The framework, policies and GRC programme are owned by the Head of Security; the engineering behind them is yours.
• Audit Evidence: Own technical evidence collection, control testing and remediation tracking. Be the person who sits with auditors and delivers clear, documented, defensible answers about the estate.
• Technical Risk: Conduct threat modelling and technical risk assessments. Feed findings and treatment options into the risk register owned by the Head of Security.
• Documentation: Build and maintain the full security documentation estate architecture diagrams, tool configurations, runbooks, incident reports, risk registers, process maps, policy library. Set the standard for what good documentation looks like.
• Security Awareness: Support the security awareness programme with technical content - phishing simulation tooling, engineering inductions, technical policy rollouts. The programme itself is owned by the Head of Security.

What We’re Looking For

• 6+ years in security engineering, enterprise security or security operations
• Deep hands‑on experience deploying, configuring, managing and troubleshooting enterprise security tools - EDR/XDR, SASE/SWG, SIEM, DLP, email security, endpoint privilege management, MDM
• Expert‑level knowledge of identity and access management SSO, SAML, OAuth, SCIM, conditional access, MFA, passwordless with proven zero trust implementation in production
• Led incident response investigations end to end - built playbooks, managed containment and drove remediation across real‑world security incidents
• Strong scripting and automation capability (Python, Bash, PowerShell) applied to detection engineering, security operations and compliance automation
• Practical experience implementing technical controls and producing audit evidence against ISO 27001, SOC 2, Cyber Essentials or GDPR
• Fluent in security frameworks and threat methodologies (MITRE ATT&CK, NIST CSF, CIS Controls, OWASP) with practical application, not just theoretical knowledge
• Experience securing cloud‑native and SaaS‑heavy environments (AWS preferred)

Highly Desirable

• Experience in iGaming, fintech or another heavily regulated industry, with understanding of gaming regulatory frameworks and player data protection
• Background in application security, API security testing, secure SDLC or product security within a platform‑based business
• Hands‑on SIEM detection engineering - writing correlation rules, building dashboards, tuning alert logic at scale
• Experience with cloud security tooling (AWS GuardDuty, Security Hub, CloudTrail, Config), SSPM, CASB or DLP platforms
• Relevant senior certifications (CISSP, CISM, GIAC GSEC/GCIH/GCIA, CySA+, vendor‑specific: CrowdStrike CCFA/CCFR, Netskope) or equivalent proven track record
• Experience mentoring engineers and building technical capability

What We Offer

At MrQ, we take pride in providing an array of fantastic benefits to our valued team members. Enjoy a competitive salary package that recognizes your hard work and dedication. Need some extra time off? We’ve got you covered with additional leave days, and we believe in celebrating life’s special moments, including your birthday, with dedicated birthday leave. Family matters to us, too, which is why we offer a generous four‑week parental leave. Your well‑being is our priority, supported by international health and life insurance. Stay motivated with wellness incentives and seize opportunities for personal and professional growth with our growth allowance. Embrace a flexible working environment that caters to your needs, and join our friendly and multinational team, where collaboration and camaraderie flourish. At MrQ, we’re committed to ensuring that your experience with us goes beyond just a job – it’s a fulfilling journey with a supportive community.

We are committed to fostering a workplace that values and celebrates diversity. We welcome individuals of all backgrounds and experiences, and we believe that a diverse and inclusive environment leads to innovation and success. We actively promote equal opportunities for all employees and strive to create a space where everyone's voices are heard and respected. Join us in our journey to build a truly inclusive workplace where every person can thrive and contribute to our collective success.