Senior Full-Stack Engineer (TypeScript, React, Node.js)

A seed-stage B2B SaaS company is building subscription infrastructure for e-commerce and needs a full-stack engineer who owns features from idea to release. The role involves working across frontend and backend using TypeScript, React, and Node.js, collaborating directly with designers and founders to shape product architecture. Responsibilities include building merchant-facing billing flows, improving developer-facing APIs and docs, turning designs into accessible UI, and maintaining simple, observable code.