Frontend Developer

GuardianStack is device intelligence and continuous authentication delivered as a single API. We stop account takeover, session hijacking, and fraud for iGaming operators, fintechs, NIS2 regulated enterprises, and SaaS platforms. We are hiring our Founding Frontend Engineer to own everything our customers see and touch, and to work directly with the founder.

Key Responsibilities

• Own the customer facing surface of GuardianStack end to end: the policy dashboard, session inspector, onboarding flows, and documentation experience.
• Design and build the hosted dashboard where customers configure policies, review flagged sessions, and monitor device intelligence signals in real time.
• Develop and maintain framework SDKs and integration snippets (React, Next.js, Vue, and vanilla JS) that make GuardianStack installable on a login surface in minutes, not days.
• Work on the client side agent that collects browser level signals, with a focus on performance, reliability across browsers, and resilience against tampering and evasion.
• Collaborate with the founder on product decisions, moving from rough concept to shipped feature quickly and iterating based on direct customer feedback.
• Build internal tooling that supports the sales motion, including audit reporting views and pilot dashboards used in customer engagements.
• Establish frontend engineering foundations: component architecture, design system, testing practices, and CI, setting the standard for engineers who join after you.
• Contribute to developer experience assets such as quickstarts, code samples, and interactive documentation that reduce integration friction for customers.

Required Qualifications

• 4+ years of experience building production frontend applications, ideally in B2B SaaS, security, fintech, or developer tools.
• Deep expertise in modern JavaScript and TypeScript, React, and at least one meta framework such as Next.js.
• Strong understanding of browser internals: storage mechanisms, the DOM, network behavior, rendering, and cross browser quirks. Experience with browser fingerprinting, bot detection, or anti fraud tooling is a major plus.
• Experience designing and shipping SDKs, embeddable scripts, or developer facing libraries where bundle size, performance, and API ergonomics matter.
• Product sense and design sensibility: you can take a problem from wireframe to polished interface without a dedicated designer.
• Comfort with ambiguity and ownership. You are energized by being the first engineer on a surface, not intimidated by it.
• Excellent communication skills and the ability to work asynchronously with a founder led team.
• Bonus: familiarity with authentication flows, session management, OWASP concepts, or compliance driven products (NIS2, DORA, PSD2).