Fullstack Engineer, Investigator Tools

Who we are: Sardine is the leading agentic risk platform for fighting financial crime. Our integrated solution unifies data across risk teams to help organizations stop fraud in real time, prevent AI-driven attacks, and automate fraud and AML operations. Sardine’s platform is strengthened by one of the fastest-growing fraud consortiums in the market, spanning more than 6 billion profiled devices, 800 million consumers, and 3 million businesses worldwide. Leading companies including FIS, GoDaddy, Intuit, Edward Jones, ZoomInfo, and Checkout.com rely on Sardine to secure and grow trust in their products. Our culture: • We hire talented, self-motivated individuals with extreme ownership and high growth orientation. • We value performance and not hours worked. We believe you shouldn't have to miss your family dinner, your kid's school play, friends get-together, or doctor's appointments for the sake of adhering to an arbitrary work schedule. • We're a remote-first team spread across time zones, so no office to report to - work from wherever helps you do your best work. Just a couple of things to keep in mind: pay is based on where you're located, and you'll need to keep a home base in the country you're hired in. So while we love the "coffee shop today, mountains tomorrow" life, this isn't a passport-optional, work-from-anywhere-on-Earth kind of remote - think flexible within your country, not borderless. Location: • Remote - United Kingdom About the role: As a Full Stack Engineer at Sardine, you will bridge the gap between complex technical backend systems and user-friendly interfaces to help us stop fraud in its tracks. This is a dynamic, high-impact role. On average, you will be working 60% on backend development and 40% on frontend development but are willing to help out wherever is needed. You will build out data-intensive applications, including advanced graph systems used to uncover complex fraud rings. You will own features end-to-end at a massive scale, ultimately empowering fraud analysts to uncover and investigate suspicious transactions faster than ever before. What you’ll be doing: Own features end-to-end: Drive the product lifecycle from determining the initial problem space and user needs, to technical modeling, UX execution, and iterative improvements based on vague requirements. Translate complexity to usability: Build out complex technical systems into intuitive, user-friendly interfaces. Build fraud-fighting tools: Develop and optimize advanced graph systems to visualize fraud rings, and build performant search tools that help analysts rapidly identify suspicious transactions. Collaborate cross-functionally: Work tightly with Design, Data, Product, and Account Management teams to align engineering output with business and user needs. Ensure system health: Proactively diagnose, triage, and resolve bugs while writing highly efficient and performant code. What you’ll need: Core technical stack: Extensive experience writing efficient, production-ready code in TypeScript, Node.js, React, Go and other server programming languages. Scale and data expertise: Proven experience working with data-intensive applications, complex workflows, and big data at scale. Pipeline proficiency: Deep background in technical data modeling and building robust production data pipelines. High-growth adaptability: The ability to thrive, execute, and deliver consistently in a fast-paced, high-growth startup environment. Independent execution: A proven track record of taking extreme ownership of ambiguous problems and independently turning them into polished, scalable features. Benefits we offer: • Generous compensation in cash and equity • Early exercise for all options, including pre-vested • Work from anywhere: Remote-first Cultur