Senior Offensive Security Engineer

• Join Monzo's Offensive Security team — curious, hands-on security professionals who think like attackers to keep Monzo and its customers safe. • Work across customer-facing products, mobile apps, cloud infrastructure, internal systems, and emerging technologies including AI. • Find weaknesses before others do through security testing, red and purple teaming, and adversarial research. • Lead offensive security projects from initial idea through to execution and reporting. • London, Cardiff, or fully remote within the UK, with ad hoc meetings in London.

• Strong attacker mindset with a natural curiosity about how systems can be broken. • Hands-on experience in offensive security across areas such as web, mobile, cloud, or infrastructure. • Comfortable working across modern tech stacks such as Kubernetes, AWS/GCP, and microservices, or excited to learn. • Able to take ownership of ambiguous problems and drive them through to impactful outcomes. • Experienced in security testing and/or holds relevant certifications such as OSCP or CREST. • Enjoys collaborating with others and influencing teams to think more securely.

• Experience with red teaming or purple teaming engagements. • Background in adversarial research on AI or emerging technologies. • Experience producing proof-of-concept exploits to demonstrate real-world risk and drive meaningful fixes.

• Lead offensive security projects from initial idea through to execution and reporting. • Simulate real-world attacks to uncover vulnerabilities across Monzo's systems, infrastructure, and products. • Partner with engineering and security teams to improve detection, response, and resilience. • Bring an attacker mindset into conversations — asking "what if?" and challenging assumptions. • Produce proof-of-concept exploits to clearly demonstrate risk and drive meaningful fixes. • Mentor others in the team and act as a highly independent technical lead on complex engagements.

We have been Monzo customers for years and have always loved their beautiful, simple app UI. We believe their product has a positive impact on millions of customers, motivating them to be more conservative with their spending and helping them save money. Monzo, as a company, has consistently grown over the past 10 years and is known for its strong company culture, generous benefits, and leadership that strives to be truly transparent and cares about its colleagues. It is a company that helps you advance your career and grow as a professional, working with great teams. If you like to join a thriving, upcoming bank and help millions of customers lead a financially sound life, Monzo gives you the opportunity to push ahead.

• Salary of £76,500–£90,000 plus performance-based incentive awards. • Flexible working hours — work in a way that fits your life. • £1,000 learning budget each year for books, training courses, and conferences. • Full home working setup provided, including a MacBook. • London, Cardiff, or fully remote within the UK, with ad hoc meetings in London.

Monzo is on a mission to make money work for everyone. Its Offensive Security team, part of the wider Security collective, works across customer-facing products, mobile apps, cloud infrastructure, and AI systems — using an attacker mindset and adversarial research to help Monzo build more secure systems and protect its customers.