Senior Full-Stack Engineer - New York - On-Site - Opportunity to join one of the Fastest-Growing and

<h3>Job Description</h3><div><p><strong>Senior Full-Stack Engineer – New York – On-Site – Opportunity to join one of the Fastest-Growing and Well-Known Fin-Tech Start-Ups in NYC </strong></p>\n<p><br /></p>\n<p>This young and agile company, building a cutting-edge commerce network is currently seeking a talented Senior Full-Stack Engineer to work on high-impact projects.</p>\n<p><br /></p>\n<p>You will assist with the continuous expansion and optimization of their services in a frontier space.</p>\n<p>This is an excellent opportunity for an experienced Full-Stack Engineer to take the next step into a challenging position with a company offering significant growth potential.</p>\n<p><br /></p>\n<p><strong>About the Company:</strong></p>\n<p><br /></p>\n<ul>\n <li>Valued at over $10bn having raised over $250m in their Series B funding in 2025.</li>\n <li>Launched in the 2020’s, this is phenomenal growth</li>\n <li>Their network has already reached more than 4.5 million people</li>\n <li>They have already acquired some smaller Fintechs</li>\n <li>They launched their new product in 2026</li>\n</ul>\n<p><br /></p>\n<p><strong>About the Senior Full Stack Engineer Vacancy: </strong></p>\n<p><br /></p>\n<p>In this position, you will:</p>\n<p><br /></p>\n<p>• Work across the full lifecycle of projects - from scoping and technical roadmapping to production and deployment</p>\n<p>• Have your say in technical conversations, code reviews, and architectural decision-making</p>\n<p>• Adapt to the demands of various projects and issues by working across the stack as needed</p>\n<p>• Use Node.js frameworks (NestJS, Hono, Express) to create and manage backend services.</p>\n<p>• Use Next.js, React, and React Native to create efficient front-end experiences.</p>\n<p>• Work together with design teams to utilise our design system on mobile and web platforms.</p>\n<p>• Create schemas, optimise queries, and guarantee data integrity using relational databases (PostgreSQL).</p>\n<p>• Put into effect and uphold observability techniques, such as distributed tracing, structured logging, and monitoring</p>\n<p><br /></p>\n<p><strong>Ideal Requirements for the Senior Full Stack Engineer Vacancy:</strong></p>\n<p><br /></p>\n<p>• Several years of professional software development experience</p>\n<p>• Strong proficiency in React, TypeScript, and modern JavaScript</p>\n<p>• Hands-on experience with Node.js backend development using frameworks like NestJS, Express, or Hono</p>\n<p>• Experience with Next.js and/or React Native for building production applications</p>\n<p>• Solid understanding of relational databases (PostgreSQL preferred), including data modeling and query optimization</p>\n<p>• Familiarity with state management patterns and libraries (Redux or similar)</p>\n<p>• Experience working with design systems and component libraries</p>\n<p>• Understanding of observability fundamentals: logging, tracing, metrics, and alerting</p>\n<p>• Experience designing systems that scale—caching strategies, async processing, API design</p>\n<p>• Proficiency with Git and modern CI/CD workflows</p>\n<p>• Strong problem-solving skills and attention to detail</p>\n<p>• Solid understanding of RESTful APIs and web services</p>\n<p>• Excellent communication and collaboration abilities</p>\n<p><br /></p>\n<p><strong>Apply to the Role:</strong></p>\n<p><br /></p>\n<p>Roles like these are snapped up very quickly, so act now if you do not want to miss out! Reply to this advert or email your CV to <span>[email protected]</span></p>\n<p><br /></p></div>