Security Architect – Design & Operations

In our world things change by the millisecond

We build the technology that creates amazing moments and better connects our customers. Ready to play your part? Join us and Be Phenomenal. Working towards the same shared goal of better connectivity, our tech teams enjoy a high degree of freedom. We love hearing ideas and seeing them come to life. With great resources, you’ll get to be part of a team at the foundations of the transformation of our business. Who knows what the next innovation will be? That’s what makes a career at Three so exciting

Since we set foot in Ireland, we’ve done things differently

Investing in infrastructure, we built a network that now connects 2.2 million customers nationwide, carrying more data than all alternative telecommunications providers combined. We take the script and rip it up, we’re a big-hearted energetic bunch, striving for a better connected life. We encourage our employees to face their weaknesses, to really open themselves up to new tasks and projects in a super-charged and rich learning environment. We want you to become the best version of yourself.

Join us as a Security Architect – Design & Operations

At Three Ireland, we’re looking for an experienced Security Architect to play a key role within our wider security and technology teams, helping to ensure security is embedded across the design and operation of our IT, Network, Cloud, and Digital services.

This is a key role where you’ll help shape how security is architected, embedded, and run, ensuring our controls are not just well designed, but measurable, resilient, and effective in practice and that they are in line with industry best practice, regulatory obligations, and the Three Ireland Security Policy.

What else it involves:

• Help shape enterprise security architecture across applications, infrastructure, networks, mobile, and cloud
• Embed secure-by-design principles across technology initiatives
• Oversee security operations, including incident response, monitoring, and managed security services#
• Act as a senior escalation point during major security incidents
• Drive risk management, resilience, and regulatory compliance (ISO 27001, NIST, NIST 2, GDPR, PCI DSS)
• Partner with IT, Network, Cloud, and external providers to deliver secure, scalable solutions
• Influence senior stakeholders by translating technical risk into business impact

The skills were looking for:

• 5+ years in senior cybersecurity roles across architecture, risk, and operations
• Strong hands-on expertise in security design and operational controls
• Experience with incident response, SOCs, and MSPs
• Broad technical knowledge across enterprise IT, networks (WAN/LAN), and cloud
• Excellent communication and stakeholder engagement skills
• Threat modelling & risk assessment
• Security architecture (application, infrastructure, cloud)
• Incident response & forensic investigation
• Vulnerability management & remediation
• Third-party security governance
• Data protection & privacy

Desirable

• CISSP
• CISM
• CRISC
• ISO 27001
• Data Protection
• PCI certifications

Benefits of Working at Three

• Flexible working with our new Hybrid model, our employees will enjoy more flexibility working from home and our office locations (3 days per week office based). Please see job description for the office location of this role.
• Competitive salary, annual performance bonus & pension contribution
• 25 days holidays plus 2.5 company days
• Annual Leave buy or sell (buy or sell up to 5 days AL each year)
• Healthcare Insurance through our flexible benefits programme
• Life assurance, phone & laptop, subsidized canteen
• Access to learning & development tools such as Coursera
• Free on-site parking

There’s a lot more to us than meets the eye.

You may think you know us, but we’re full of surprises. Intrigued? Join us and Be Phenomenal.

Apply now at: https://www.three.ie/careers #Jobs

At Three, we are committed to equity, diversity and inclusion. As Ireland’s largest mobile telecommunications provider, we provide a better connected life for our diverse customer base, and want our teams to reflect this. We welcome and celebrate all identities and strive to create a culture of belonging where employees can thrive as their authentic selves. If you do not ‘tick every box’ in this job description, you likely have other valuable skills that would make you a great fit for one of our teams. If you feel this role is for you, then please apply! #Jobs

If you require reasonable adjustments for your interview, please let us know when scheduling your interview, or alternatively, please email [email protected] Apply now at Three, a Phenomenal career awaits!