Java Full Stack Lead Developer in United Kingdom

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role This is where security meets innovation at enterprise scale. As a security engineer, applications at WRITER, you'll be building the security foundations that protect the AI systems powering some of the world's most recognizable brands. You'll work at the intersection of application security, AI infrastructure, and developer enablement—partnering with engineering teams to embed security into every line of code while ensuring our platform remains both powerful and trustworthy. The opportunity is massive: you'll help define how enterprise AI applications are secured, from threat modeling our LLM architectures to building automated security controls that scale across our growing platform. This isn't about saying "no"—it's about finding creative ways to say "yes, and here's how we do it securely." You'll tackle challenges that most security engineers never encounter: securing AI agents, protecting training data pipelines, and designing controls for systems that didn

About the Team OpenAI’s Applied AI Engineering team helps organizations turn frontier AI capabilities into safe, reliable, and high-impact production systems. We work with customer executives, product and engineering teams, security leaders, and transformation teams to identify valuable opportunities, accelerate technical implementation, and scale what works. Enterprise deployments are defined by complexity rather than any one industry: existing architectures, diverse data environments, security and governance requirements, multiple stakeholder groups, and organization-wide change. We turn lessons from these deployments into better products and reusable patterns for customers everywhere. About the Role As an Applied AI Engineer you will partner directly with leading organizations to design, build, and deploy AI systems that deliver measurable business outcomes. You will combine deep technical judgment, hands-on engineering, and customer leadership to take ambitious ideas from use-case selection and architecture through prototyping, evaluation, production launch, and scale. You will write and debug code, build evaluation systems, resolve complex integrations, and guide decisions involving model behavior, reliability, latency, cost, safety, security, governance, and operational readiness. Success is measured by production systems, sustained adoption, and meaningful customer impact—not simply activity or successful demonstrations. This is a rare opportunity to work on consequential real-world deployments at the frontier of AI while directly influencing how OpenAI’s products evolve. This role is based in London. We use a hybrid work model of 3 days in the office per week and offer relocation assistance to new employees In this role, you will: Partner directly with enterprise customers to identify high-value opportunities and translate them into technical architectures, implementation plans, evaluation strategies, and measurable success criteria. Design, build, and deplo

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role This is where security meets innovation at enterprise scale. As a security engineer, applications at WRITER, you'll be building the security foundations that protect the AI systems powering some of the world's most recognizable brands. You'll work at the intersection of application security, AI infrastructure, and developer enablement—partnering with engineering teams to embed security into every line of code while ensuring our platform remains both powerful and trustworthy. The opportunity is massive: you'll help define how enterprise AI applications are secured, from threat modeling our LLM architectures to building automated security controls that scale across our growing platform. This isn't about saying "no"—it's about finding creative ways to say "yes, and here's how we do it securely." You'll tackle challenges that most security engineers never encounter: securing AI agents, protecting training data pipelines, and designing controls for systems that didn