Jobs in United Kingdom

Application Security Head in London

29 active opportunities · Updated October 2026

Explore current application security head jobs in London. Filter by work mode, employment type, experience, department, date posted and distance.

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📍 London, Greater London, United Kingdom· Full-time
✓ Quality checkedCompany trend -100%

Synthesia is the world’s leading AI video platform for business, used by over 90% of the Fortune 100. Founded in 2017, the company is headquartered in London, with offices and teams across Europe and the US. As AI continues to shape the way we live and work, Synthesia develops products to enhance visual communication and enterprise skill development, helping people work better and stay at the center of successful organizations. Following our recent Series E funding round, where we raised $200 million, our valuation stands at $4 billion. Our total funding exceeds $530 million from premier investors including Accel, NVentures (Nvidia's VC arm), Kleiner Perkins, GV, and Evantic Capital, alongside the founders and operators of Stripe, Datadog, Miro, and Webflow. About the role You will focus on friction points around primarily backend issues for all teams in Engineering (90 Engineers). How should we do inter-service testing? Some teams are using monorepo, others aren’t. How can we bring overall stability up? Generally steering BE in the right direction. In the near future, standardising things across all of Engineering and bringing R&D teams (another 40 Engineers and Researchers) closer. You will have ownership of projects that span quarters, requiring you to have the ability to break a problem down into small steps that can be delivered and validated iteratively. You will evaluate your own work, leveraging our data pipeline and frameworks that we have established to understand the impact your features have on our commercial objectives and pivoting where necessary. You will consider the long-term direction of Engineering, making sure that we are developing the engineering capabilities that will allow us to stay ahead of the challenges we are likely to encounter in 12-18 months' time. You will work end-to-end, from our client application written in React to our monolithic backend written in Python, and lead projects that span across multiple teams. What we're looking

PythonReactAIGo
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📍 London, England, United Kingdom· Full-time· Remote
✓ High-confidence listingCompany trend +37.5%
Quick readStrong listing-quality and freshness signals

🚀 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 Are you passionate about ensuring the highest quality for cutting-edge generative AI applications? As a software quality engineer at WRITER, you'll play a critical role in shaping the reliability, performance, and trustworthiness of our AI-powered work orchestration platform. You’ll be at the forefront of defining and implementing rigorous quality strategies for our enterprise-grade LLMs and AI agents, directly impacting how hundreds of global companies unlock transformational value through AI. This is a unique chance to dive deep into the unique challenges of AI quality assurance and make a tangible difference in a rapidly evolving field. This is a hybrid role based out of our London, San Francisco, Seattle, and New York City hubs. You will report directly to the director of engineering. 🦸🏻‍♀️ What you'll do Define and implement comprehensive quality assurance strategies and test plans for our AI agents and LLM-powered applications, ensuring exceptional prod

TypeScriptPythonAWSAzure
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📍 London, England, United Kingdom· Full-time· Remote
✓ High-confidence listingCompany trend +37.5%
Quick readStrong listing-quality and freshness signals

🚀 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 Are you passionate about ensuring the highest quality for cutting-edge generative AI applications? As a software quality engineer at WRITER, you'll play a critical role in shaping the reliability, performance, and trustworthiness of our AI-powered work orchestration platform. You’ll be at the forefront of defining and implementing rigorous quality strategies for our enterprise-grade LLMs and AI agents, directly impacting how hundreds of global companies unlock transformational value through AI. This is a unique chance to dive deep into the unique challenges of AI quality assurance and make a tangible difference in a rapidly evolving field. This is a hybrid role based out of our London, San Francisco, Seattle, and New York City hubs. You will report directly to the director of engineering. 🦸🏻‍♀️ What you'll do Define and implement comprehensive quality assurance strategies and test plans for our AI agents and LLM-powered applications, ensuring exceptional prod

TypeScriptPythonAWSAzure
O
📍 London, Greater London, United Kingdom· Full-time
✓ Quality checkedCompany trend -100%

About the Team The Applied AI team is responsible for ensuring the safe and effective deployment of Generative AI applications for developers and enterprises. We act as a trusted advisor and thought partner for our customers, working to build an effective backlog of GenAI use cases for their industry and drive them to production through strong technical guidance. As the leader of our ADEs in the Large Enterprise segment, you’ll help companies transform their business through solutions such as customer service, automated content generation, and novel applications that make use of our newest, most exciting models. About the Role We are seeking an Applied AI Engineering leader to ensure the technical success of our most strategic Large Enterprise customers across EMEA. In this role, you will manage the entire implementation journey, ensuring seamless platform integration. As the voice of our customers, you will align technical teams to deliver a consistent and exceptional experience throughout the customer lifecycle. Success will be measured by live production applications, increased API adoption, and impactful customer stories that demonstrate the value of our technology. This role is open in both our London and Munich offices. 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: Own the strategy and operating model of the Large Enterprise Applied AI team, ensuring alignment with company objectives and the evolving needs of our customers. Lead, build, and mentor a team of high-performing ADEs to deliver exceptional customer outcomes, as demonstrated by production customer applications and increased API adoption. Serve as the technical advocate for our customers, synthesizing their needs to develop the Research and Applied Product/Engineering roadmaps. Act as the primary technical escalation point during development, fostering trust and maintaining direct communication with executive-level

AWSRestAIRust
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📍 London, United Kingdom· Full-time
✓ High-confidence listingCompany trend -97.1%
Quick readStrong listing-quality and freshness signals

At Snowflake, we are powering the era of the agentic enterprise. To usher in this new era, we seek AI-native thinkers across every function who are energized by the opportunity to reinvent how they work. You don’t just use tools; you possess an innate curiosity, treating AI as a high-trust collaborator that is core to how you solve problems and accelerate your impact. We look for low-ego individuals who thrive in dynamic and fast-moving environments and move with an experimental mindset — who rapidly test emerging capabilities to discover simpler, more powerful ways to deliver results. At Snowflake, your role isn't just to execute a function, but to help redefine the future of how work gets done. Observe is a SaaS powerhouse enabling businesses to investigate modern distributed applications 10x faster. Now, as a core part of Snowflake, we've reached a major milestone in the evolution of the AI Data Cloud. By bringing AI-powered observability directly into the Snowflake ecosystem, we've created the first truly unified platform for telemetry and business data. We are looking for a Sales Development Representative to join us at the ground floor of this expansion. At Observe, the SDR program isn't just a department—it's our leadership pipeline. We view our SDRs as the next wave of Account Executives, and we invest in you accordingly. If you are looking to turbocharge a career in tech sales, this is your training ground. We provide the tools, the mentorship, and the roadmap to turn high-potential talent into elite sales professionals. What You'll Experience: Deep Investment: From our 2-week intensive bootcamp to weekly 1-1 mentorship and bi-weekly strategy sessions, we prioritize your growth over everything else. The "In-the-Trenches" Culture: Our leadership team doesn't manage from the sidelines. We work alongside you to hone your business acumen and accelerate your path to productivity. A True Meritocracy: We celebrate diversity and reward results. Our goal is to give

AIGoRustSalesforce
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📍 London, England, United Kingdom· Full-time· Remote
✓ High-confidence listingCompany trend +37.5%
Quick readStrong listing-quality and freshness signals

🚀 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 As a deployment engineer at WRITER, you'll be at the forefront of expanding human capacity through superintelligence. This isn't just a technical role; it's a deeply influential one where you'll partner directly with our leading enterprise customers. Your expertise will be crucial in uncovering their unique business challenges and architecting AI-powered solutions that leverage our powerful platform and enterprise-grade LLMs. You'll transform complex needs into tangible, high-impact applications, creating champions and driving tangible business results. Your builder's mentality and passion for bringing cutting-edge AI into the hands of real users will directly shape the future of work for some of the world's largest companies. This is a critical role that directly impacts our customers' success and product evolution. You'll contribute significantly to WRITER's mission, working with a dynamic team to push the boundaries of what's possible with generative AI. Thi

W
📍 London, England, United Kingdom· Full-time· Remote
✓ High-confidence listingCompany trend +37.5%
Quick readStrong listing-quality and freshness signals

🚀 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 As an AI engineer at WRITER, you'll be at the forefront of shaping how enterprises harness superintelligence. This isn't just about theory; you'll be building tangible AI solutions that power the future of work for hundreds of the world's leading companies. Your work will directly impact the performance, scalability, and ethical alignment of our cutting-edge LLMs and AI agents, enabling businesses to unlock unprecedented levels of productivity and innovation with AI that is truly grounded in their data. This role can be hybrid in our London hub. You'll report to the head of AI engineering. 🦸🏻‍♀️ What you'll do Architect, develop, and deploy high-performance, scalable AI applications into production environments, ensuring robust integrations with our end-to-end platform. Drive the development of intelligent agents and AI-powered features, translating complex research into practical, impactful solutions for our customers. Collaborate closely with research scien

PythonAWSAzureGCP
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📍 London, England, United Kingdom· Full-time· Remote
✓ High-confidence listingCompany trend +37.5%
Quick readStrong listing-quality and freshness signals

🚀 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 At WRITER, our enterprise customers are building mission-critical AI applications that transform how their businesses operate. As a senior support engineer, your top priority is helping our developer personas and technical users succeed with our platform. You'll act as a leading voice for our enterprise support function, handling intricate customer issues directly while working in a complex and ambiguous environment to drive impactful value across our customers' businesses. You'll collaborate closely with Customer Success, Education, Product, Engineering, and Sales to create great experiences and help customers get the most out of the platform. By leveraging an automation-first mindset, you'll scale our support operations and use our own AI tools to solve problems faster and more efficiently. This role is available for hybrid work in our New York City and London hubs. and you will report directly to the manager of support engineering. 🦸🏻‍♀️ What you'll do Own

PythonAWSGCPAI
DC
📍 London, England, United Kingdom· Full-time
✓ High-confidence listing
Quick readStrong listing-quality and freshness signals

About Dot Collective We are a new generation consultancy based across UK and EU and founded on the premises of the engineering excellence and empowering people to make an impact. We work with all modern tech stacks and typically run agile scrum on all our projects. About you Are you passionate about data and its transformational powers? Do you like being able to make a huge difference in a limited period of time? We might be just the right place for you. Your key skills and capabilities: · Implementing cloud-native data platforms · Engineering scalable and reliable pipelines · Good knowledge of distributed computing with Spark · Understanding of cloud architecture principles and best practices · Hands-on experience in designing, deploying, and managing cloud resources · Excellent python and SQL skills · Agile ways of working · Experience in cloud automation and orchestration using tools such as CloudFormation or Terraform · Monitoring and performance tuning of cloud-based applications and services Nice to haves: (MLOps): Model Deployment & Serving – Deploy and manage ML models using MLflow, Azure ML, SageMaker, or similar, ensuring scalability and performance. Monitoring & Retraining – Set up model drift detection, performance monitoring, and automated retraining ML Pipelines & CI/CD – Automate end-to-end ML workflows We expect you to have some knowledge about how to architect, design, develop, deploy, and operate a data platform. Our promise to you We will always see you as a human being and will do our very best to support your needs and wellbeing – well-designed co-working and collaboration spaces, remote working patterns that work for you, parenting leave, sabbatical

PythonSQLAzureCI/CD
DC
📍 London, England, United Kingdom· Full-time
✓ High-confidence listing
Quick readStrong listing-quality and freshness signals

About Dot Collective We are a new generation consultancy based across UK and EU and founded on the premises of the engineering excellence and empowering people to make an impact. We work with all modern tech stacks and typically run agile scrum on all our projects. About you Are you passionate about data and its transformational powers? Do you like being able to make a huge difference in a limited period of time? We might be just the right place for you. A little bit about the role Over the past 18 months, The Dot Collective has successfully established a dedicated Data Architecture practice , laying the foundation for robust, scalable, and innovative data solutions. This practice underpins our commitment to delivering high-quality, data-driven outcomes for clients across diverse sectors. As we continue to grow, we are seeking a Data Solution Architect to play a pivotal role in shaping and implementing cloud native data and AI platforms that make a real impact. Your Key Skills and Capabilities Work with technical teams to clarify and refine architecture so as to maintain consistency during deliver Recognise ways to describe the structure and behaviour of applications used in a business, with a focus on how they interact with each other and with business users or actors Help the customer articulate their requirements and formulate a suitable solution architecture Proven experience of designing and building data platforms. A strong understanding of modelling data and how to make data work at scale A grasp of modern data governance is also appreciated Have an understanding of Microservices and Serverless architectures. Be able to describe the structure and behaviour of the technology platform that underpins user applications and understand on-premise, Cloud hosting and end-user compute Knowledge of open source, open standards and cloud technologies An understanding of architectural concepts, methodologies and approa

MicroservicesAgileScrumAI
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📍 London, England, United Kingdom· Full-time
✓ High-confidence listing

£107K – £262K/yr

Quick readStrong listing-quality and freshness signals

SpaceXAI’s mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company’s mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: The Sandbox service team at SpaceXAI builds and maintains a secure, scalable system that gives our models safe, controlled access to computational environments. This infrastructure powers critical workloads across training and product, enabling models to run code, build software, interact with tools, and even control applications with user interfaces. We provision containers and virtual machines on large-scale clusters, granting models interactive control over these remote environments. Our work spans the full stack: from orchestrating massive jobs and resource scheduling at the cluster level, to fine-tuning filesystem performance on nodes. The Sandbox service enables Grok to safely run and test code in real-time for user queries, and supports reinforcement learning in training, where models interactively explore tools ranging from compilers to productivity apps. BASIC QUALIFICATIONS: Expert knowledge of Rust, C++ or Go Familiarity with Python Deep experience with either Linux or Windows systems (familiarity with both is a strong plus) Experience with virtualisation and containerisation technologies (e.g., cgroups, KVM, gVisor, QEMU) Solid knowledge of the networking stack COMPENSATION AND BENEFITS: £107,000 -

PythonLinuxAIC++
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📍 London, England, United Kingdom· Full-time
✓ High-confidence listing

£107K – £262K/yr

Quick readStrong listing-quality and freshness signals

SpaceXAI’s mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. Our team is small, highly motivated, and focused on engineering excellence. This organization is for individuals who appreciate challenging themselves and thrive on curiosity. We operate with a flat organizational structure. All employees are expected to be hands-on and to contribute directly to the company’s mission. Leadership is given to those who show initiative and consistently deliver excellence. Work ethic and strong prioritization skills are important. All employees are expected to have strong communication skills. They should be able to concisely and accurately share knowledge with their teammates. ABOUT THE ROLE: As an ideal candidate you have a good understanding of how highly scalable and reliable production infrastructure is built. Most of our backend infrastructure is written in Rust. So familiarity with a compiled language such as C++, Rust, or Go is highly beneficial. RESPONSIBILITIES: Build the SpaceXAI API that serves our models to developers worldwide Own the end-to-end system responsible for high-throughput inference, handling billions of tokens per minute with low latency and high availability, including model serving infrastructure, request routing, SDK development, rate limiting, observability, and efficient scaling BASIC QUALIFICATIONS: Expert knowledge of either Rust or C++ Experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems Knowledge of service observability and reliability best practices Experience in operating commonly used databases such as PostgreSQL, Clickhouse, and MongoDB PREFERRED SKILLS AND EXPERIENCE: Experience with LLM inference engines and serving frameworks (e.g., SGLang, TensorRT, vLLM) Experience designing or building with agent SDKs and agent orchestration frameworks Experience with Docker, Kubernetes, and containerized applicatio

SQLPostgreSQLMongoDBDocker
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📍 London, England, United Kingdom· Full-time
✓ High-confidence listing
Quick readStrong listing-quality and freshness signals

About the Job: LaunchDarkly is looking for a VP, EMEA Sales to lead and scale our regional sales organization as we enter a period of high growth and expand across a growing portfolio of products. Reporting to the Chief Revenue Officer, this leader will own new business and expansion revenue across EMEA. This is a high-impact leadership role for a builder and operator who can turn regional insight into a focused go-to-market strategy, build a repeatable pipeline engine, and create the operating discipline needed for predictable growth. The VP will lead a multi-level sales organization and partner closely with Marketing, SDR/BDR, Solutions Engineering, Customer Success, Partnerships, Enablement, and Revenue Operations. This is an exciting opportunity to help shape the next phase of LaunchDarkly’s growth by bringing our AI Runtime Control capabilities to more customers across EMEA, helping organizations build, deploy, and manage AI-powered applications with greater control and confidence. Responsibilities: Own new business and expansion revenue across EMEA. Set regional go-to-market strategy across segmentation, territories, coverage, capacity, hiring, and resources. Build repeatable pipeline across outbound, inbound, account-based, and partner channels. Establish operating rhythms for pipeline inspection, forecasting, deal progression, performance, and business reviews. Deliver accurate forecasts and visibility into pipeline, deal health, productivity, risks, and opportunities. Lead and develop Sales Directors, Managers, and Account Executives while building a strong management bench. Drive consistent sales methodology, account planning, qualification, and pipeline hygiene. Engage in strategic deals through executive relationships, value selling, negotiation, and deal strategy. Scale land-and-expand across new logo, adoption, cross-sell, and expansion motions. Partner with Solutions Engineering and Customer Success to improve deal quality, adoption, reten

GitAIGoDevOps
DC
📍 London, England, United Kingdom· Full-time
✓ High-confidence listing
Quick readStrong listing-quality and freshness signals

Here’s a summary of the role: Build cloud software that matters, grow your technical depth, and use modern AI tooling to do your best work. This is a hands-on engineering role for someone who enjoys solving product problems, writing clean code, and helping services run reliably at scale. You’ll work on secure, scalable microservices and APIs using TypeScript, AWS , and modern engineering practices. You’ll be part of a collaborative product engineering team where you can own features, contribute to design discussions, support production systems, and keep growing across backend, cloud, and AI-assisted development workflows. Here’s a breakdown of what you’ll do, not all of it, just the important stuff: Design, build, test, and improve backend services and APIs using Node.js, TypeScript, and AWS . Take ownership of well-defined features from planning through release, including code quality, deployment, and production support . Work closely with product managers, designers, and other engineers to turn requirements into practical, reliable solutions. Contribute to technical design conversations, code reviews, and engineering standards that keep the team moving well. Use AI tools to speed up research, coding, debugging, testing, and documentation, while checking outputs carefully and applying sound judgment. Help keep systems secure, observable, and maintainable by improving monitoring, reliability, and day-to-day development practices. These are the essentials you’ll need to get an interview: 3 to 5 years of professional software engineering experience building production applications in an agile environment. Strong backend development skills with Node.js and TypeScript, including experience building APIs or microservices. Experience with React or Angular in a product engineering environment. Hands-on experience with

TypeScriptReactNode.jsAngular

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