This position is listed on behalf of a partner company, which manages all applications and next steps. Our partner is looking for a Senior Software Engineer - Full Stack based in the United States. The Senior Software Engineer will design, develop, and optimize high-performance web applications that make financial services more accessible and user-friendly. This role combines deep frontend expertise with full-stack capabilities, contributing to scalable products that simplify lending and debt management. You will build and enhance modern web experiences using React and Next.js while collaborating with backend engineers to deliver cohesive end-to-end features. Working closely with Product Managers, Designers, and engineering colleagues, you will lead projects from technical planning through implementation and release. You will also drive experimentation, improve platform observability, and help maintain the reliability and performance of production systems. The position offers the opportunity to contribute to a modern technology stack within a remote-first, startup-oriented environment that values ownership, innovation, and teamwork. You will have room to influence technical decisions, improve engineering practices, and deliver meaningful product outcomes while continuing to grow professionally.