Application Security Engineer at Writer | London, UK

About WRITERWRITER is at the forefront of empowering the world's leading enterprises with AI-driven solutions. Our mission is to enhance human capabilities through superintelligence, proving that transformative, reliable AI is achievable. By bridging IT and business teams, we enable organizations to undergo enterprise-wide transformations. Hundreds of renowned companies, including Mars, Marriott, Uber, and Vanguard, utilize WRITER's comprehensive platform to build and deploy AI agents based on their unique data, powered by our enterprise-grade LLMs. With a valuation of $1.9B and support from top-tier investors like Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is solidifying its role as a pioneer in enterprise generative AI.Founded in 2020, and with offices in San Francisco, New York City, Austin, Chicago, and London, our dynamic team is dedicated to innovative thinking and swift action. We invite talented, dedicated builders and visionaries to join us in shaping the future of work through AI. About the RoleJoin us as a Security Engineer specializing in Application Security at WRITER, where security innovation meets enterprise-scale challenges. You will lay the foundational security measures to safeguard the AI systems that support some of the most recognizable brands globally. Collaborating closely with engineering teams, your role will be pivotal in integrating security into every aspect of our coding processes, ensuring our platform remains robust and trustworthy.This is a tremendous opportunity to shape the security landscape for enterprise AI applications, from threat modeling our LLM architectures to creating scalable automated security controls across our growing platform. Embrace the challenge of discovering creative solutions that allow us to proceed securely. You will encounter unique hurdles that most security engineers may never face, including securing AI agents, shielding training data pipelines, and designing controls for systems that are still in their infancy.This position offers the flexibility of remote work within the US or a hybrid model from our San Francisco or New York City offices, with direct reporting to the Head of Security Engineering.

About WRITERWRITER empowers the world's leading enterprises to harness AI-driven workflows. Our mission is to amplify human potential through advanced intelligence. We're demonstrating this potential with robust, reliable AI solutions that unite IT and business teams, facilitating comprehensive transformation across enterprises. With WRITER's integrated platform, numerous organizations including Mars, Marriott, Uber, and Vanguard are crafting and deploying AI agents rooted in their proprietary data and enhanced by WRITER's enterprise-grade large language models (LLMs). Valued at $1.9 billion and supported by top-tier investors such as Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is swiftly establishing itself as the forefront leader in enterprise generative AI.Established in 2020, with offices in San Francisco, New York City, Austin, Chicago, and London, our team is ambitious and agile, seeking intelligent, dedicated innovators and builders to join us in our quest to shape the future of work with AI. About the RoleSeize the opportunity to influence AI governance at one of the most rapidly expanding companies in enterprise AI. As a Security Specialist for Governance, Risk, and Compliance (GRC) at WRITER, you will construct the frameworks that ensure our AI platform secures the trust of the world's leading enterprises. This role goes beyond mere compliance; you will develop the compliance framework that enables WRITER to scale both securely and efficiently while maintaining a pace of innovation.The potential here is remarkable: you will operate at the intersection of AI, security, and business facilitation, helping to define governance standards for AI systems that are relatively new. You will lead audit engagements for SOC 2, ISO 27001, and other essential certifications, respond to client security assessments critical to major contracts, and create policies and controls to safeguard our AI models and the sensitive information flowing through them. Your role will involve translating complex regulatory mandates into actionable, business-aligned security measures while collaborating with Engineering, Legal, Product, and Sales teams to ensure WRITER can penetrate highly regulated sectors without sacrificing our momentum.This position can be performed remotely within the US or in a hybrid capacity from our San Francisco or New York City offices, reporting directly to the Head of Security.

About WRITER WRITER builds AI technology for some of the world’s largest enterprises, helping them unlock new ways of working. Companies like Mars, Marriott, Uber, and Vanguard use WRITER’s platform to create and deploy AI agents tailored to their own data and needs. With a valuation of $1.9 billion and support from investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is recognized as a leader in enterprise generative AI. Founded in 2020, WRITER has offices in San Francisco, New York City, Austin, Chicago, and London. The team values ambition and innovation, working together to shape the future of AI-powered work. Role Overview: AI Deployment Engineer The AI Deployment Engineer will join WRITER’s London office in a hybrid capacity. This role combines technical expertise with strategic client engagement. The engineer will work directly with enterprise customers to understand their business challenges and design AI solutions using WRITER’s platform and large language models. Responsibilities include translating complex client requirements into practical applications, collaborating with IT and business teams, and helping clients achieve measurable results. The role also involves supporting customer success and influencing the evolution of WRITER’s products. Key Responsibilities Partner with enterprise clients to identify business needs and challenges Design and implement AI-powered solutions using WRITER’s platform and LLMs Translate requirements into effective, real-world applications Work closely with both IT and business stakeholders Support clients in adopting and championing AI within their organizations Contribute feedback to help shape the future direction of WRITER’s products Location This is a hybrid position based in London, UK.

Role Overview Writer is hiring a Security Engineer focused on Detection and Response for the London office. This position centers on protecting systems and data by identifying, analyzing, and mitigating security threats. What You Will Do Monitor for suspicious activity and potential breaches across Writer’s infrastructure. Analyze incidents and coordinate responses to minimize risk and impact. Work with fellow engineers and analysts to design and implement security measures. Help select and refine tools and processes for incident detection and response. Collaboration and Impact This role works closely with the broader cybersecurity team. Decisions and recommendations from this position directly influence Writer’s security posture and resilience against attacks.

We are seeking an experienced and dynamic Senior Manager of Solutions Architecture to join our team in London. In this pivotal role, you will lead the design and implementation of innovative solutions that align with our clients' needs and business objectives. Your expertise will be crucial in driving architectural vision and ensuring the delivery of scalable, robust solutions.As a leader, you will collaborate closely with cross-functional teams, providing guidance and mentorship to junior architects while fostering a culture of excellence and innovation. Join us to make a significant impact in the world of solutions architecture and elevate our service offerings.

Join our dynamic team at Shawbrook as an Application Security Engineer. In this pivotal role, you will be responsible for safeguarding our applications by implementing robust security measures throughout the software development lifecycle. Your expertise will help identify vulnerabilities and enhance our overall security posture, ensuring our systems remain resilient against evolving threats.

Join Our Team as a Security EngineerAt incident.io, we are transforming incident response with our cutting-edge AI platform, dedicated to minimizing response times and enhancing reliability. Our comprehensive solution integrates on-call management, incident response, AI SRE, and status updates into one seamless platform, empowering teams to act swiftly, reduce outages, and keep their customers informed.Since our inception in 2021, we have successfully assisted over 1,500 organizations, including renowned names like Netflix, Airbnb, and Block, in managing over 500,000 incidents. Each month, thousands of engineers, product managers, and support staff rely on incident.io to restore services efficiently, maintain alignment during high-pressure situations, and focus on what truly matters.We are a rapidly expanding, ambitious team that values our customers, the quality of our product, and the magic we create together. With $100M raised from prestigious investors like Index Ventures, Insight Partners, and Point Nine, along with contributions from top executives in the tech industry, we’re poised for significant growth.Your RoleAs our inaugural Security Engineer, you will play a vital role in our product teams, ensuring application security is integrated from the foundational stages. Collaborating closely with engineers, you will identify vulnerabilities before they progress to production, mentor your peers on secure coding practices, and foster a culture where security is a primary focus.This position offers a unique opportunity to work at the intersection of security and engineering, contributing to the design and development of secure systems that align with our commitment to customer satisfaction.

Join Palantir, a pioneering force in data-driven software solutions, as a Senior Application Security Engineer. Our mission is to empower organizations to make critical decisions that save lives, enhance security, and drive innovation. As part of our esteemed Product Security team, you will collaborate closely with cross-functional teams to implement secure-by-design principles across our product offerings. Your expertise will be crucial in conducting comprehensive security reviews, threat modeling, and guiding the architectural design to ensure robust security measures are integrated from the ground up. You will lead strategic security initiatives that enhance our entire product suite and help identify and mitigate potential vulnerabilities through advanced analysis techniques. This is an opportunity to make a significant impact in a company dedicated to transforming the world through technology.

Join our dynamic team at ion as an Application Security Engineer, where you will play a crucial role in safeguarding our applications and data. You will collaborate with development teams to identify vulnerabilities and implement security best practices, ensuring that our software is resilient against threats.Your expertise will help us create secure coding standards and guidelines, conduct security assessments, and perform code reviews. You will be at the forefront of enhancing our security posture and contributing to the overall success of our projects.

Role overview Three UK is seeking a Regulatory Manager to join the team in London. The position centers on ensuring the company meets all relevant regulatory obligations and helps the business stay aligned with current compliance standards. Key responsibilities Oversee compliance activities throughout the organization Maintain communication with regulatory authorities when required Create and apply policies that support regulatory compliance Promote sound business practices by implementing effective compliance measures Location This role is based in London.

Role overview Xero Limited is seeking a Senior Engineer to join its UK Regional Team, based in London at 7 Devonshire Square. This position focuses on shaping features for the UK market, connecting technical work directly to customer needs and business outcomes. Senior Engineers at Xero handle complex challenges that span multiple products, balancing regional requirements alongside global strategy. Team structure and collaboration The team includes an Engineering Manager, Lead Engineers, and Engineers, all reporting to the General Manager of Engineering for the UK. Collaboration is a core part of the role. Senior Engineers work closely with product owners and peers across Xero, designing, building, and delivering solutions that have real impact. Projects and technical scope Current projects span the full Xero platform, including Payments, Accounting, and Payroll. This role provides exposure to a broad range of products and technical domains within Xero’s suite. Work environment Xero holds a Great Place to Work UK accreditation. Flexible work arrangements are available: choose remote, hybrid, or office-based work in London, Milton Keynes, or Manchester. Offices are designed to support collaboration and connection. Some travel may be needed to coordinate with global teams and support international partnerships. Requirements Curiosity and drive to solve customer problems, delivering clear business value across technical areas Adaptability in learning new domains and navigating unfamiliar codebases Ability to work with stakeholders and build consensus across distributed teams Commitment to high-quality engineering practices, producing scalable and maintainable code Comfort in high-visibility situations, using strong communication to engage stakeholders and broaden influence Experience with modern programming languages and frameworks, along with a solid understanding of software engineering fundamentals

Join Three UK as a Regulatory Lead and play a pivotal role in shaping our regulatory strategies. You will be at the forefront of navigating complex regulatory landscapes, ensuring compliance, and advocating for our interests in the telecommunications sector.

About WRITERAt WRITER, we empower the world's leading enterprises to harness the potential of AI-driven operations. Our mission is to enhance human capabilities through superintelligence, demonstrating its feasibility with reliable AI that bridges IT and business teams for comprehensive organizational transformation. With our robust end-to-end platform, numerous renowned companies such as Mars, Marriott, Uber, and Vanguard are developing and implementing AI agents rooted in their organizational data, propelled by WRITER's enterprise-grade LLMs. As a company valued at $1.9B and supported by top-tier investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly establishing itself as the frontrunner in enterprise generative AI.Founded in 2020 with office hubs in San Francisco, New York City, Austin, Chicago, and London, we are a dynamic team that thinks big and acts swiftly. We are in search of innovative and diligent builders to join us on our mission to redefine the future of work with AI. About the RoleWe are seeking a knowledgeable customer success professional who will oversee the deployment and activation success across a diverse portfolio of customers. By immersing yourself in your customers' organizations, you will gain insights into their business goals and formulate programs, communities, and frameworks that translate AI investments into tangible results. Collaborating closely with a Transformation lead, you will identify the most suitable WRITER capabilities for each use case and design strategies that promote impactful adoption: establishing champion networks, conducting tailored workshops, and advising clients on how to scale their AI initiatives over time.The ideal candidate will possess a proactive, builder's mindset regarding customer success—taking the initiative to create conditions for engagement rather than waiting for customers to reach out.This is a hybrid role based in our London office.‍ What You'll DoTake ownership of activation and platform successDevelop a deep understanding of each customer's unique use cases, business objectives, and success metricsCollaboratively build custom AI solutions with customers, translating their specific use cases into workflows that generate measurable business impactDesign and implement activation strategies that foster significant platform adoption and drive business outcomesEstablish champion programs, office hours, usage dashboards, tailored training, and workshops

Join Three UK as a Regulatory Manager, where you will play a vital role in shaping our regulatory strategies and ensuring compliance with industry standards. You will collaborate with various stakeholders to develop and implement policies that support our business objectives while adhering to regulatory requirements.

Three UK seeks a Partnerships Executive in London to help develop and maintain key relationships with partners. The position supports the company’s goal of providing reliable connectivity and a positive customer experience. Role overview This role centers on building and nurturing strategic partnerships. The Partnerships Executive will work with internal teams and external organizations to strengthen collaboration and ensure shared objectives are met. Key responsibilities Establish and manage partnerships that align with Three UK’s business goals Maintain ongoing communication with partners to support mutual success Contribute to initiatives that enhance customer connectivity and satisfaction Location This position is based in London.

Role overview The Regulatory Lead at Three UK plays a key part in guiding compliance and shaping company policy to meet telecommunications regulations. Based in London, this position works closely with teams across the business, providing regulatory expertise and ensuring that company practices align with industry requirements. What you will do Advise on regulatory issues that impact the telecommunications sector Collaborate with internal teams to maintain compliance with laws and standards Assist in developing and updating internal policies to match current regulations Support the business in understanding and applying regulatory changes Location This role is based in London.

Join Our Vision at WriterAt Writer, we empower leading enterprises to harness the potential of AI-driven work. Our mission is to amplify human capabilities through superintelligence. By delivering reliable AI solutions, we unite IT and business teams to drive transformative changes across organizations. Our comprehensive platform is used by industry giants such as Mars, Marriott, Uber, and Vanguard, enabling them to create and implement AI agents that leverage their proprietary data, powered by Writer's enterprise-level LLMs. With a valuation of $1.9B and support from top-tier investors like Premji Invest, Radical Ventures, and ICONIQ Growth, Writer is solidifying its status as a frontrunner in enterprise generative AI.Founded in 2020, with strategic hubs in San Francisco, New York City, Austin, Chicago, and London, our dynamic team thrives on innovation and speed. We seek intelligent, driven individuals to join us in shaping the future of work through AI. Role OverviewWe are on the lookout for a dedicated customer success professional who will take charge of deployment and activation success across our customer portfolio. You will immerse yourself within your clients' organizations, grasp their business goals, and develop programs, communities, and frameworks that translate AI investments into tangible results. Collaborating closely with a Transformation Lead, you will identify the appropriate Writer capabilities for each unique use case and craft and implement strategies that foster significant adoption, including building advocacy networks, facilitating tailored workshops, and guiding clients on scaling their AI initiatives over time.The ideal candidate possesses a proactive, builder's mindset in customer success: you will not wait for customers to engage; instead, you will create the environment for engagement.This opportunity is a hybrid role based in our London hub.

Role OverviewAt Theodo, we are assembling a dynamic team of talented engineers who are passionate about producing exceptional code consistently while enhancing their technical skills. This position is ideal for individuals who excel at tackling complex technical challenges, learning from their exceptional colleagues, and diving deep into the code every day.As part of a high-performing team, you will engage with fast-paced, real-world client projects. This entails thoughtful collaboration, clear communication, and a proactive approach to overcoming obstacles, both for yourself and your teammates.We seek engineers who ask insightful questions, leverage their teammates' knowledge, and understand how to obtain the resources necessary to perform at their best.The Cloud Engineer Role involves building with AWS Serverless technologies. This is a client-facing role where you will participate in discussions and planning with our external clients, engaging in both technical and business-oriented conversations. While our primary stack consists of AWS Serverless and TypeScript, you will have the opportunity to gain experience with diverse methodologies and occasionally explore different technologies.

About WriterWriter is at the forefront of AI-driven enterprise transformation, where leading organizations harness the power of superintelligence. Our mission is to enhance human capabilities through advanced, reliable AI solutions that unify IT and business sectors, facilitating profound organizational change. Hundreds of renowned companies, including Mars, Marriott, Uber, and Vanguard, leverage Writer's comprehensive platform to create and implement AI agents rooted in their own data, powered by our enterprise-grade LLMs. With a valuation of $1.9B and support from prestigious investors such as Premji Invest, Radical Ventures, and ICONIQ Growth, Writer is swiftly establishing itself as the premier authority in enterprise generative AI.Established in 2020, our offices span San Francisco, New York City, Austin, Chicago, and London. Our team operates with ambition and agility, seeking intelligent, dedicated innovators to join us in shaping a future of work enriched by AI. About the RoleWe are in search of a visionary AI Transformation Lead to act as a strategic partner for our high-priority Fortune 100 clients. This pivotal role transcends typical software integration; you will help major organizations fundamentally reconsider their operational methodologies. Positioned at the crossroads of business strategy and cutting-edge technology, you will translate the capabilities of the Writer platform into tangible financial performance and guide executives through the transition to an AI-centric operational framework.This is a unique opportunity to develop the roadmap for enterprise AI transformation. You will not merely oversee accounts; you will drive the next industrial revolution by assisting C-suite executives in progressing from AI pilot projects to realizing full-scale value. Your contributions will directly inform Writer's product development and shape how premier brands utilize superintelligence to enhance human productivity.This position is offered as a hybrid role based in our London office, reporting to the Director of AI Transformation and Success.‍ What You’ll DoOversee a customer portfolio while spearheading ROI and value initiatives alongside a Customer Success Manager focused on adoption strategies.Serve as a strategic transformation partner for Fortune 50-100 clients, establishing a vision and defining the JTBD framework with executive teams to promote AI adoption.Develop and maintain relationships with C-suite executives to drive engagement and ensure successful implementation of AI solutions.

About the AI Security InstituteThe AI Security Institute stands as the world's largest and most well-funded team focused on comprehending the risks associated with advanced AI technologies and effectively translating that knowledge into actionable strategies. Nestled in the core of the UK government, we maintain direct communication lines to No. 10 (the Prime Minister's office) and collaborate with cutting-edge developers and governments across the globe.Our mission is to ensure that governments play a pivotal role in the responsible advancement of AI. The UK AISI is uniquely positioned to mobilize governmental action effectively. With our extensive resources, unmatched agility, and international influence, we offer an unparalleled opportunity to shape the trajectory of AI development and governmental policy.The deadline for applying to this role is February 22, 2026, end of day, anywhere on Earth.About the Team The Cyber and Autonomous Systems Team (CAST) is dedicated to researching and mapping the rapidly evolving landscape of AI capabilities. Our goal is to inform critical security decisions aimed at mitigating risks associated with loss of control over frontier AI systems. We are committed to preventing potential harms stemming from high-impact cybersecurity capabilities and advanced autonomous AI systems. Our team comprises a diverse mix of high-velocity generalists and technical experts from prestigious organizations such as Meta, Amazon, Palantir, DSTL, and Jane Street. Recent projects include the creation of comprehensive model evaluation suites, including Replibench, the world's most extensive evaluation suite designed to understand the risks of a model autonomously replicating itself across the internet. We also engage in pre-deployment evaluations of leading AI models.