Javascript jobs in United Kingdom

Discover your future at Citi

Working at Citi is far more than just a job. A career with us means joining a team of more than 230,000 dedicated people from around the globe. At Citi, you’ll have the opportunity to grow your career, give back to your community and make a real impact.

We are Citi’s Application, Platform and Engineering team, a start-up with the exciting mission of shaping the direction of travel for the entire bank under the Chief Technology Office, by defining the tech and engineering strategy for the bank. We are a team of talented engineers, product managers and tech SMEs, taking ambiguous concepts and making them real by engineering cutting edge products at planetary scale! We are solely focused on the most modern technology and engineering disciplines such as generative AI, cloud, security, modern app stacks (with Golang, Gatekeeper), open source and the latest and greatest in the Kubernetes ecosystem.

Generative AI is a growing space, as a result, we ask that you share with us any specific AI engineering projects utilising LLMs that you’re proud of in your application. Ideally these projects should show off complex and clever architectures or a systematic evaluation of an LLM’s behaviour.

You might be a good fit if you

• Bring your deep-dive applicationsecurityengineering expertise from building production systems
• Thrive in a results-driven environment, where flexibility fuels impact
• Be a game-changer, ready to step beyond your designated role
• Love the synergy of pair programming? So do we!
• Seize the opportunity to secure AI applications at scale. Jump in!
• A relentless passion to learn more about AIsecurity, LLM attacks, and bringing your knowledge to shape Citi's secure AI future.

• Build secure AI products from 0-1-Engineerproduction-grade, business-facing AI platforms withsecuritybuilt-in from day one
• Ethical hacking and red team activities- Conduct penetration testing, vulnerability research, and attack simulation to make our products bulletproof
• Design and buildsecuritytools and frameworks- Create automatedsecuritysolutions that scale across fast-paced development cycles
• Secure novel AI attack surfaces- Identify and mitigate LLM-specific vulnerabilities, prompt injection attacks, and AI modelsecurityrisks through hands-on testing
• Lead "shift left"security- Embedsecuritypractices throughout our rapid development lifecycle while maintaining velocity
• Mentorsecuritypractices- Guide otherengineers on secure coding, vulnerability remediation, andsecurity-first thinking

• Proficient in Golang
• Production system builder withsecurityfocus- proven track record of architecting and building secure, large-scale production applications and business-facing platforms from the ground up
• Ethical hacking and penetration testing expertise- hands-on experience finding and exploiting vulnerabilities, conducting red team exercises, and thinking like an attacker to strengthen defenses
• State-of-the-artsecurityengineeringwith Go, Python, JavaScript - you build bothsecuritytools and secure production systems in fast-paced environments
• HashiCorp Vault mastery- deep experience writing custom plugins, creating secrets engines, implementing dynamic credentials, and extending Vault functionality for enterprise-scale secrets management
• Enterprise authentication & authorization- designing and implementing OAuth, JWT, RBAC, and complex identity systems with fine-grained access controls in business-critical applications
• APIsecurityand threat modelling- securing REST/GraphQL APIs, conducting threat assessments, and implementing advancedsecuritypatterns in high-traffic production systems
• AI/MLsecurityand vulnerability research- understanding of LLM vulnerabilities, modelsecurity, prompt injection attacks, and AI-specific threat vectors through hands-on testing
• Securityautomation and tooling– automating manualsecurityprocesses
• Cloud-nativesecurity- securing containerized applications in Kubernetes, service meshsecurity, and cloud-nativesecuritypatterns at enterprise scale
• Incident response and forensics- experience investigating, analyzing, and responding tosecurityincidents in live production systems

• We do not have boundaries betweensecurityengineering and product development, and we expect all our technical staff to contribute to both as needed.
• We take a product-focused approach tosecurityand care about building solutions that are robust, scalable, and easy for developers to use.
• We enjoy working in a fast-paced team tackling cutting-edgesecurityproblems by constantly testing and learning.
• We enjoy pair programming for oursecuritytools; we are lean in our approach and remove bureaucracy where we see it.
• We believe in delivering secure solutions fast, iterating and pivoting as we go, rather than defining the perfectsecurity framework upfront.

This is a unique role that will put you in the position to be part of a new venture and actively drive change. Every day there will be new challenges that will help you develop new skills that can drive your career.

By joining Citi London, you will not only be part of a business casual workplace with a hybrid working model (up to 2 days working at home per week), but also receive a competitive base salary (which is annually reviewed), and enjoy a whole host of additional benefits such as:

• 27 days annual leave (plus bank holidays)
• A discretional annual performance related bonus
• Private Medical Care & Life Insurance
• Employee Assistance Program
• Pension Plan
• Paid Parental Leave
• Special discounts for employees, family, and friends

Visit our Global Benefits page to learn more.

Alongside these benefits Citi is committed to ensuring our workplace is where everyone feels comfortable coming to work as their whole self, every day. We want the best talent around the world to be energized to join us, motivated to stay and empowered to thrive.

Citi is an equal opportunity employer, and qualified candidates will receive consideration without regard to their race, color, religion, sex, sexual orientation, gender identity, national origin, disability, status as a protected veteran, or any other characteristic protected by law.

If you are a person with a disability and need a reasonable accommodation to use our search tools and/or apply for a career opportunity review Accessibility at Citi.

View Citi’s EEO Policy Statement and the Know Your Rights poster.