Senior Full Stack Engineer

Role Overview Cato Networks is hiring a Full Stack Engineer in London to support the development of cloud-based security products. This role focuses on building and improving scalable applications that serve clients worldwide. What You Will Do Work with teams across disciplines to define, design, and deliver new product features Develop and enhance applications for performance, scalability, and reliability Troubleshoot and debug issues in both front-end and back-end components Ensure applications respond quickly and handle client requests efficiently Location This position is based in London, England, United Kingdom.

Join the forefront of cloud networking and security!Cato Networks has pioneered the integration of enterprise networking and security into a singular, centralized global service delivered via the cloud. Founded by the esteemed networking and security innovator Shlomo Kramer, and backed by early investors from notable firms like Palo Alto Networks and Trusteer, Cato has established a groundbreaking product category known as ‘SASE’, projected to reach a staggering market size of $28.5 billion by 2028.Don’t miss your chance to be part of a transformative journey with a company that is rapidly ascending to become the global leader in secure cloud platforms and enterprise networking solutions.At Cato Networks, we are revolutionizing networking and security as a secure cloud service and are seeking a talented and experienced Product Manager to join our Access & Identity team. In this critical role, you will drive Cato’s ZTNA and remote access product initiatives, further solidifying our leadership in the SASE domain.

Role Overview Join us as a Full Stack Engineer at Theodo, where you'll have the chance to work directly with clients, including CEOs and co-founders, to understand their unique requirements and develop tailored solutions. You'll engage in hands-on learning from day one, guided by seasoned developers who will mentor you in managing your own projects. As you progress, you'll take on greater responsibilities, mentor junior developers, and become a key technical advisor within your team. If you excel at solving complex problems and are eager to expand your technical skill set while tackling new challenges, this is the opportunity for you.In this role, you will be part of a small, dynamic team focused on creating innovative web and mobile applications for our clients. Collaboration with agile and technical coaches will be essential as you build scalable solutions using the latest technologies.

(Applicants must be based in London, UK)About the RoleWe are on the lookout for talented and driven Full Stack Engineers to join our innovative team at Herondata. As a pivotal member of our fast-growing AI startup, you will play a crucial role in crafting elegant technical solutions that address our customers’ diverse challenges. If you are passionate about delivering high-quality code and are eager for a rewarding new challenge, we want to hear from you!Key ResponsibilitiesIn this hands-on role, you will focus on developing products that provide real solutions for our customers. Your responsibilities will include:Creating, maintaining, and enhancing backend services and APIs.Developing and designing new UI and web components.Integrating with third-party services and AI models.Assisting in bug triage, investigating production incidents, and contributing to postmortems and root cause analyses.Engaging in code reviews and collaborating with both technical and non-technical teams and stakeholders.What We SeekOur ideal candidate will:Be passionate about building impactful solutions: You enjoy shipping code rapidly, valuing MVPs and customer outcomes more than perfection. You take ownership of the deployment of your work.Excel at solving complex technical challenges: You can break down problems into simple, effective solutions, maintaining a fact-based and thoughtful approach.Focus on scalability: You prioritize impactful action while ensuring scalable infrastructure and engineering processes. You bring innovative practices to improve our systems.Contribute within our tech stack: We are currently utilizing Python/Flask/FastAPI for the backend, Terraform/GCP/AWS for infrastructure, and React/JavaScript/TypeScript/Vercel for the frontend. Your ability to contribute and enhance our stack is essential.

Overview Join Tipalti, a dynamic fintech company located in the heart of London, dedicated to automating financial workflows for small and medium-sized businesses. Our engineering culture is robust, collaborative, and focused on making a tangible impact for our clients. As a Senior Full-Stack Engineer, you will merge hands-on engineering skills with a product-oriented mindset. You will define requirements, engage in technical discussions, and influence user experiences while managing the entire software development lifecycle. Responsibilities Develop robust, efficient, and well-tested code across the technology stack. Create new features and enhancements that align with product priorities. Participate in design and architecture discussions, shaping the technical direction. Review code with team members, ensuring clean code practices and quality standards are met. Collaborate closely with Product Managers to clarify requirements and propose solutions. Proactively identify questions, edge cases, and assist in refining specifications. Provide technical insights into prioritization and product decisions. Communicate effectively with designers, engineers, and stakeholders. Share knowledge and mentor colleagues as needed. Engage with external partners and vendors for integration work when necessary. Requirements Experience building across the full stack and a keen interest in learning new technologies. A passion for writing clean, maintainable, secure, and well-tested code. Strong collaboration skills and a preference for team environments. A curiosity about customer needs and the ability to translate them into technical solutions. A commitment to continuous learning and knowledge sharing within the team. Preferred Tech Skills Proficiency in JavaScript / TypeScript, Node.js, and React (or similar frameworks). Experience with REST APIs or microservices architecture. Familiarity with MongoDB. Knowledge of cloud services, particularly AWS. Why Join Tipalti? An open, inclusive, and supportive engineering culture.‍ Opportunities to build products utilized by some of the world’s fastest-growing companies. Equity options in a late-stage scale-up.

Join Faculty as a Full Stack Software Engineer and be part of a dynamic team that is pushing the boundaries of technology. We are looking for an innovative and driven individual who thrives in a fast-paced environment and is passionate about building scalable applications.As a Full Stack Software Engineer, you will work on both front-end and back-end development, collaborating closely with cross-functional teams to deliver high-quality software solutions that meet our clients' needs.

Who We AreAt Intropic, we are revolutionizing financial intelligence by merging profound market expertise with cutting-edge AI technology. Established in the heart of London’s Canary Wharf, our mission is to simplify complex data into actionable insights. Our workplace culture thrives on values such as truth-seeking, speed, and accountability, shaping our collaborative and innovative environment. We prioritize integrity and impact, encouraging curiosity and independent thinking. If you are passionate about tackling challenges, driven by innovation, and eager to enhance your intelligence alongside a team of brilliant minds, Intropic is the perfect place for you to bring your ideas to life.Who We Look ForAs a dynamic fintech start-up with a successful product lineup, we are on the brink of launching our next groundbreaking initiative. We seek individuals who excel at solving complex, open-ended problems across various domains; our engineers are expected to engage in more than just routine tasks. A typical week might involve debugging Python code, implementing infrastructure changes, engaging with early adopters, and collaborating on strategic planning with team leads. We value talent over traditional resumes; if you are interested, we would be thrilled to hear from you!

Pharmacy2U, the UK's largest online pharmacy, serves over 1.8 million NHS patients and has been a trusted name in digital healthcare for 25 years. As a certified B Corp and Great Place to Work, the company is committed to high social and environmental standards, transparency, and a supportive workplace. Role overview This Full Stack Engineer position is based in London with a hybrid work model. Expect to work from the central London office twice each month. The role is permanent and full-time. Core hours are 09:30 to 16:00, with flexibility to adjust your schedule around these times. What you will do Share technical responsibility for both current and new services. Collaborate with engineers, clinicians, algorithm developers, and Quality Analysts to deliver solutions that are reliable and well-tested. Take part in an out-of-hours on-call rota when required. On-call duties are scheduled fairly and include additional compensation. Who we’re looking for The team is seeking a skilled, detail-oriented Full Stack Engineer who values collaboration and problem-solving. A strong commitment to quality and a desire to improve healthcare for millions are important in this role. Why join Pharmacy2U? Work alongside a team focused on enhancing patient care through technology. Join an organization recognized for its positive culture and social responsibility. Receive a comprehensive benefits package and a competitive salary based on experience. Benefit from supportive and flexible working arrangements.

Corgi builds insurance products for tech startups, using artificial intelligence to power underwriting and streamline processes. The company operates as a fully licensed carrier, has raised $108M, and is expanding into the UK and EU. The platform relies on Django and Stripe, with a focus on fast, AI-driven solutions. Role overview This Full-Stack Engineer position is based in London. The team values people who turn ideas into working products, whether through side projects, weekend builds, or tools that real users rely on. Engineers here often work independently, taking projects from concept to deployment without waiting for a detailed roadmap. Self-starters who enjoy building and shipping quickly will feel at home. Requirements Track record of independently developing and launching projects that reached users Comfort working across the stack, especially with Django and Stripe Ability to deliver results in hours or days, not long cycles Adaptability and willingness to change direction as needed Strong opinions, paired with openness to better solutions Focus on outcomes and results over job titles How we work Decisions happen quickly, prioritizing action over perfection Products and process changes launch regularly, not just on a quarterly basis Ship-and-iterate mindset: feedback and improvement come after launch High energy is expected during product pushes and quieter times Transparency: decisions are made openly Internal competition is encouraged, with top performers raising the bar This is a hands-on role for builders who want to make an impact. Behaviors that lead to removal Office politics, avoiding responsibility, or gossip Taking direct feedback personally instead of constructively Adding unnecessary overhead instead of streamlining Missing deadlines after committing to them How to apply Send links to GitHub, personal sites, live projects, or shipped work Resumes are not accepted Email applications to: sergio@corgi.com If you cannot show shipped work, this role is not a fit Location and compensation London-based, with on-site or hybrid options Base salary: £75,000 to £140,000, plus equity Compensation is based on ability to ship, not job titles

Join our dynamic Platform Performance team as a Full-Stack Software Engineer with 2–4 years of experience, and help us create fast, scalable solutions for millions of users globally.In this role, you will engage in all aspects of the software stack—enhancing frontend performance, optimizing backend services, and improving the responsiveness, reliability, and overall user experience of our interfaces. You will collaborate with a dedicated team of engineers and product managers to identify performance bottlenecks, contribute to architectural enhancements, and help advance our design system.This position is a fantastic opportunity for a driven engineer who is eager to expand their skillset in a fast-paced environment and make a significant impact at scale.Freelancer.com is the largest freelancing and crowdsourcing platform in the world, connecting over 80 million users across 247 countries and territories. Our platform empowers businesses, entrepreneurs, and individuals to collaborate with skilled professionals globally, turning ideas into reality more efficiently than ever.Our ambitious mission is to create one billion jobs worldwide by enabling people to work for themselves and build sustainable online careers. Every feature we develop and every performance enhancement we implement brings us closer to realizing this unprecedented opportunity.

Join our dynamic team at hyperexponential as a Full Stack Engineer, where you will be instrumental in developing innovative software solutions using Kotlin and React. This role involves collaborating with cross-functional teams to design, implement, and maintain high-quality web applications that meet our clients' needs. You will have the opportunity to work on exciting projects that push the boundaries of technology while fostering your professional growth.

Our MissionAt Omnea, we are transforming the way enterprise businesses function, focusing on the most challenging aspects: procurement. Here, a single purchase can extend for months, entail over 50 emails, and involve multiple departments such as Finance, Legal, Security, and IT just for approval.With an investment of $75M from Khosla Ventures, Insight Partners, and Accel, we aim to revolutionize this process. Our AI-driven platform integrates all stakeholders, ensuring that buying is swift, secure, and efficient. It offers a centralized location for requests, automated approvals and renewals, real-time supplier risk assessment, and complete visibility into spending.The procurement sector represents a $7B+ untapped market, and our growth underscores the opportunity: we have increased our annual recurring revenue (ARR) tenfold to double-digit millions within just 18 months and gained the trust of large enterprises like Spotify, MongoDB, Monzo, and Albertsons. We are now recognized as the 4th fastest growing startup in Europe.Our team previously scaled Tessian (a leading cybersecurity technology company supported by Sequoia, Balderton, and Accel, acquired after Series C), comprising ex-founders and operators who have successfully grown unicorns, delivered top-tier products, and achieved outstanding execution. You will collaborate with industry leaders including Ben, Abs, Sabrina, and Rebe.What We're Looking ForWe seek talented, product-focused full-stack software engineers to drive Omnea's next growth phase.In the past 18 months, we have accelerated our revenue tenfold, tripled our customer base, and maintained a retention rate exceeding 99% with enterprise clients such as Spotify, Wise, Albertsons, Adecco, and McAfee. Our talent standards are exceptionally high — it took over 10,000 interviews to recruit our first 50 team members. We are now expanding from a low double-digit count to over 200 enterprise clients, aiming for another tenfold increase in revenue in the next 2 to 3 years.This is an exciting opportunity to join us at a pivotal moment: we have achieved product-market fit, yet there is still ample room for you to influence our trajectory.

Join Our Team at 9finAt 9fin, we are revolutionizing the global debt markets with our cutting-edge AI platform, addressing a massive asset class valued over $145 trillion.Despite the extensive and critical nature of debt markets, they have historically relied on fragmented data sources, PDFs, and manual processes. Our innovative solution consolidates proprietary credit data, in-depth analyses, and efficient workflows, creating a unified platform for global market operations.Currently, more than 300 prestigious institutions, including leading global banks, asset managers, private equity firms, law firms, and advisory firms, utilize 9fin. Our rapid growth, particularly in the US market, is supported by an exceptional retention rate, driven by our comprehensive workflow adoption.We are at a pivotal moment in our journey, with strong product-market fit and a burgeoning global demand, positioning 9fin to become the leading platform for debt markets worldwide.Your Role and ResponsibilitiesCollaborate within a cross-functional team to design systems, create proof of concepts, and implement new features, including APIs, data processing, and automation, while working closely with Product and Client teams.Engage in development and engineering for backend services and web application tools within the 9fin platform.Act as a vital contributor in project teams by participating in code reviews, engaging with peers, and offering innovative ideas during research and experimentation with new technologies.Enhance the 9fin codebase by identifying opportunities for automation, refactoring, and documentation to increase efficiency.Work across a variety of web platforms, including financial data modeling, access-control logic, environmental data capture, integration with ML/AI services, data visualization, and automation systems.Foster collaboration and effective teamwork, engaging with domain experts from 9fin’s financial, legal, and editorial departments, and clearly communicating technical concepts to non-technical stakeholders.Benefit from a robust developer experience framework, featuring automated preview environments, feature flags, and well-maintained non-production environments, facilitating rapid iteration and feedback.

About WexlerWexler is at the forefront of revolutionizing litigation through advanced AI technology. Our mission is to develop the most effective AI system for legal disputes globally. We collaborate with some of the largest law firms, assisting them in navigating complex cases, identifying winning strategies, and organizing the multitude of documents and facts that come with each case. Based in London, we are a dynamic and rapidly expanding legal AI company, trusted by prominent firms like Clifford Chance, HSFKramer, Goodwin, and Addleshaw Goddard to uncover critical facts that can sway the outcome of cases.Having secured $5.3M in Seed funding from esteemed investors including Pear VC, Seedcamp, and The LegalTechFund, we are poised for significant growth. Our comprehensive AI platform is designed to manage, resolve, and prevent legal disputes for Enterprise law firms and Fortune 500 companies. As we expand at an impressive rate of 10x year-over-year, we continue to partner with leading firms each month. Our system processes millions of documents to extract objective, cross-referenced facts, enabling litigators to win more cases while significantly reducing their workload. This commitment ensures every client receives the representation they deserve.As AI transforms the legal landscape, Wexler stands out as the premier generative AI platform tailored specifically for the intricacies of litigation. Our rapid growth is a testament to the effectiveness of our approach.About the RoleWe are looking for a driven full-stack engineer to join our team and work alongside the founders to design, develop, and scale Wexler's document analysis systems, which are powered by our cutting-edge fact extraction engine. In this role, you will collaborate closely with the founding technical team, contributing significantly to our product's technical architecture and the realization of our ambitious product roadmap.As a Software Engineer, you will be instrumental in shaping the culture of our technical organization, learning from experienced Software and Machine Learning Engineers. You will be given the opportunity to quickly take on more responsibilities, with a clear pathway to leadership roles in the future.Please note that we currently have two open positions for this role.Key Responsibilities:Design, develop, and scale full-stack applications that enhance Wexler's document analysis capabilities.Create customer-facing features, internal tools, and DevOps infrastructure to support our expanding platform.Collaborate with AI engineers to incorporate LLM capabilities into production-ready software systems.Build robust and scalable backend systems using modern technologies.

Join Our Innovative Team!INFINIT, a dynamic fintech scale-up founded in 2023, is making waves across Europe and the Americas. Our mission is to transform the landscape for small and medium enterprises (SMEs) by harnessing the power of AI.We are committed to creating an all-in-one operating system that centers around banking, enabling small business owners and their teams to effortlessly manage and improve all facets of their operations with the assistance of AI agents.By focusing on specific industries, we deliver customized, high-impact solutions and develop innovative AI products that unlock significant growth opportunities for our clients. With global operations and ambitious expansion plans, we aim to redefine the fintech landscape for SMEs worldwide.Embark on the INFINIT journey with us as we revolutionize the SME economy and make a meaningful impact through cutting-edge innovation The RoleWe are looking for a talented Full Stack Software Engineer to propel our product development cycle. This role is grounded in the belief that exceptional engineers do more than just write code; they build comprehensive solutions. Your main responsibility will be to bridge the gap between business requirements and technical execution, quickly translating high-level objectives into polished, deployable features.You will be expected to question requirements, adopt a product-first mindset within the engineering team, and ensure that every line of code contributes tangible value. This position requires strong software engineering skills and keen product judgment to prioritize and deliver high-impact features in a fast-paced environment.

About the RoleWe are seeking a talented Full Stack Web Engineer to take ownership of ThreatAware's digital presence. As a key member of the Marketing team, you will play an instrumental role in shaping our website, landing pages, conversion funnels, and web-based tools. You have a passion for creating fast, visually stunning, and conversion-optimized web experiences, caring for every pixel and millisecond. If you thrive at the intersection of engineering and marketing and want to make a direct impact on how a leading cybersecurity brand is represented online, this opportunity is for you.Why Join ThreatAware?At ThreatAware, we provide security teams with a comprehensive source of truth for every device and tool within their organization. With over 150 integrations, deployment in under 30 minutes, and real-time visibility across entire IT estates, we are trusted by sectors like finance, legal, energy, and healthcare to understand their security posture.As we scale new heights, we are leveraging six years of precise cyber asset data combined with AI to revolutionize how security teams interrogate their data, automate workflows, and proactively manage risks before they escalate. You will craft the web experiences that narrate this journey and convert visitors into loyal customers.Your ResponsibilitiesTake charge of the technical aspects of ThreatAware's online presence.Develop and maintain a high-performance, secure, and accessible marketing website along with high-converting landing pages for demand generation campaigns.Implement and oversee analytics and tracking systems (GA4, HubSpot) to measure performance, conduct A/B testing, and optimize based on insights.Create interactive web tools, resource hubs, and engaging experiences that foster visitor interaction and conversion.Collaborate closely with the Brand & Creative Lead and the Demand Generation team to bring campaigns and product narratives to life online.What We Are Looking ForProficiency in TypeScript — you will be using it daily, so it should feel second nature.A keen eye for design and detail. You have experience building responsive, accessible, and aesthetically pleasing web experiences.Hands-on experience with analytics: GA4 implementation, HubSpot integration, conversion tracking, and A/B testing.Familiarity with CMS platforms, backend services, APIs, and serverless architecture.Bonus: Experience with Next.js and React, or a background in product-led growth web experiences.

Join Our MissionAt Omnea, we are transforming the way enterprises conduct business, particularly focusing on procurement - a process often mired in delays, excessive emails, and the involvement of multiple departments such as Finance, Legal, Security, and IT. Our aim is to streamline this complex journey.Having successfully raised $75M from leading investors including Khosla Ventures, Insight Partners, and Accel, we are poised to revolutionize the procurement landscape. Our AI-driven platform integrates all stakeholders and processes, ensuring that purchasing is quick, secure, and efficient. Features include a unified request system, automated approvals and renewals, real-time supplier risk assessments, and comprehensive spend visibility.The procurement sector represents a $7B+ untapped market, and our rapid growth is indicative of this potential: we've achieved a tenfold increase in ARR to reach double-digit millions in just 18 months, earning the trust of global leaders like Spotify, MongoDB, Monzo, and Albertsons. We are proud to be recognized as the 4th fastest growing startup in Europe.Our team boasts a wealth of experience, having previously scaled Tessian, a notable cybersecurity firm backed by Sequoia, Balderton, and Accel, and acquired post-Series C. Our personnel includes former founders and operators who have propelled unicorn startups, launched exceptional products, and operated at the highest standards. You will collaborate with esteemed leaders such as Ben, Abs, Sabrina, and Rebe.Your RoleWe seek an outstanding, product-focused full-stack software engineer to become a vital part of our engineering team and assist in scaling Omnea. Our ambition is to expand from a handful of clients to over 200 enterprise customers while achieving tenfold revenue growth in the next 2-3 years. You will play a key role in propelling our product, team, and company forward as we transition from a startup to a scale-up.This is an exhilarating time to join us, as we’re on the brink of significant growth! As a Series A startup with $25M raised from Accel, Point Nine, First Round, and numerous esteemed founders and industry specialists, we've cultivated an extraordinary and dedicated team — each member being a top achiever in their previous roles.

At Elliptic, we are at the forefront of combating illicit cryptocurrency activities, having traced and disrupted over $21.8 billion in crypto laundering across various blockchains. Our work spans from monitoring sanctioned nation-states to dismantling organized crime networks that utilize token swaps and unregulated exchanges. Our compliance and investigations teams leverage our solutions to track and screen transactions with an impressive 99% market coverage.Our Customer Platform is pivotal in achieving this at an enterprise scale. We are dedicated to building a secure customer environment and robust platform foundations, empowering teams to deliver confidently while ensuring that Elliptic remains enterprise-ready.We are actively seeking a talented Full-Stack Software Engineer to join our team, focused on designing and developing exceptional customer-facing experiences and platform services that facilitate key functionalities including authentication, governance, user management, and operational tooling.Your ImpactAs a Full-Stack Software Engineer on the Customer Platform team, your contributions will be critical in delivering secure, scalable features that enhance the user experience for Elliptic customers, enabling product teams to build and release safely. You will collaborate extensively across frontend and backend systems, working alongside designers and fellow engineers to translate enterprise requirements into reliable, user-friendly experiences.Through your efforts, you will significantly contribute to establishing Elliptic as the premier choice for enterprises and financial institutions by fortifying the operational infrastructure and development platform upon which our business relies.Your ResponsibilitiesDevelop and maintain full-stack features across web UI and APIs, from initial design to production deployment.Engage with a diverse array of platforms, standards, and paradigms including Auth0, OAuth2, SAML, SCIM, and event-driven architectures.Implement secure customer-facing functionalities such as login/signup workflows, user management, governance, and enterprise features.Design and enhance backend services and APIs for shared platform components to support Elliptic’s growth (e.g., authentication/authorization, API gateways, and related services).Collaborate with other product teams to streamline and secure integration with Customer Platform capabilities.Participate in technical design reviews, planning sessions, and code reviews, ensuring high quality and clarity in the development process.Your Qualifications3–6 years of software development experience building production services in TypeScript/Node.js (or similar) and modern web applications (React or equivalent).Proven experience with both frontend and backend technologies.

Join the Edra TeamAt Edra, we're tackling one of the most challenging issues in enterprise AI: the gap between generic AI models and specific company processes. Our mission is to develop AI agents that not only understand how these processes operate but also enhance their efficiency.As a Series A startup, with backing from Sequoia and other prestigious venture capitalists, we are expanding our team in both New York and London. Our team consists of highly skilled engineers, AI researchers, and strategists who share a commitment to excellence, believing that remarkable individuals are the cornerstone of our success.Your ImpactWe are on the lookout for passionate Full Stack Engineers who have a strong dedication to software craftsmanship. You will focus on thoughtful API design, robust data modeling, and user interfaces that provide a seamless experience for both users and fellow engineers. Your role will involve creating a comprehensive platform, workflows, user experiences, integrations, and observability tools that ensure our AI solutions are effective in real-world applications. As an early member of the engineering team, you'll not only influence our product development but also help shape our engineering culture, tooling decisions, and technical foundations.We value a deliberate and thorough approach to our work. We believe in integrating the building and shipping processes; you will transition from concept to production, taking full responsibility for your outcomes. Our priority is to deliver thoughtful solutions rather than rushing fragile implementations, viewing velocity and quality as mutually beneficial rather than opposing forces.Key ResponsibilitiesDesign and implement platform systems using Python (FastAPI), including API contracts, database schemas, and infrastructure, alongside creating high-quality user experiences with TypeScript and React, focusing on clean component design, strong typing, and maintainable front-end architectures.Develop shared TypeScript and Python libraries, component systems, and internal tools that enhance the productivity of the engineering team. You will define and uphold best practices, shared types, and contracts across front-end and API boundaries.Fully own your projects: gather context, manage dependencies, and drive tasks to completion independently, without waiting for a product manager to assign tickets. Your day may include designing a schema in the morning, creating a React component in the afternoon, and troubleshooting a deployment issue by the end of the day.Contribute to the product's vision and design. Collaborate closely with design teams, critically assess interface choices, and participate in weekly product meetings to gain insights into how customers and deployed engineers utilize what you create.Maintain and build connectors, integrations, and tools that ensure our platform continuously evolves and meets user needs.