Senior Full-Stack Engineer to Continue Development of Existing Production SaaS Platform

Senior Full-Stack Engineer Needed to Continue Development of Existing SaaS Platform I am the founder of SphereCare, a relationship intelligence SaaS platform that helps businesses strengthen relationships with past customers through automated email marketing, direct mail, reminders, communication tracking, AI-assisted content, and customer engagement. This is NOT a new project. The application is already built and has a production customer using the platform. I am looking for a senior engineer to continue development, improve reliability, and become a long-term technical partner if we work well together. Current Technology React TypeScript Node.js PostgreSQL REST APIs Google OAuth Mailgun Stripe Click2Mail OpenAI Current Priorities The first phase of work includes: Complete Gmail integration Fix email sending Implement email history Implement reply tracking Improve logging and error handling Complete Stripe integration Finish Click2Mail integration Continue feature development and bug fixes The application already contains: Authentication Customer management Dashboard Contact profiles AI integration PostgreSQL database Existing backend APIs This is continuation work—not a rebuild. Documentation I have prepared professional documentation for this project including: Engineering Transition Brief Technical architecture overview Feature inventory Current project status Development priorities Existing integrations NDA Intellectual Property Assignment Agreement The selected engineer will receive these documents before beginning work. What I'm Looking For I'm looking for someone who: Writes clean, maintainable code Thinks like a software engineer—not just a coder Communicates well Can recommend better architectural approaches when appropriate Is comfortable working on an existing codebase Is interested in building a long-term working relationship I value quality over speed. If you're simply trying to finish tickets as fast as possible, this probably isn't the right project. If you enjoy improving products, solving problems, and helping build a SaaS platform for the long term, I'd love to talk with you. When applying, please include: Similar SaaS platforms you've worked on. Experience with React, Node.js, PostgreSQL, and TypeScript. Experience integrating third-party APIs. Your preferred development workflow. Why you think you'd be a good fit for this project. Important: Before access is granted to the source code, repository, technical documentation, or production credentials, the selected candidate will be asked to sign a Mutual Non-Disclosure Agreement (NDA). The engineer selected for the project will also sign an Independent Contractor & Intellectual Property Assignment Agreement to ensure all work created for SphereCare is owned by Ironwood Group, LLC.