Principal Full Stack Engineer | $90-$120/hr + Remote | Inc. 5000 Award-Winning, High-Growth Coaching Company

We are looking for a hands on Principal Full Stack Engineer who can lead a small development team while owning complex product and architectural work. This is a player-coach role: you will write and review production code, make pragmatic architecture decisions, guide engineers and contractors, and drive delivery in close partnership with Product and the existing platform architect. A defining requirement is proven experience building the proprietary AI capabilities of an AI SaaS product from the ground up.

We need someone who has engineered the AI application layer and its production systems, not someone whose AI experience is limited to connecting a chatbot or third-party AI API to an existing application. Using foundation models or third-party model APIs is compatible with this requirement; the differentiator is ownership of the underlying AI product architecture and functionality. Lead a small engineering team: set technical direction within agreed product priorities, mentor developers, delegate work, run effective code/design reviews, coordinate contractors, remove blockers, and maintain accountability for quality and delivery.

Build proprietary AI product capabilities: design and implement retrieval and RAG pipelines, embeddings/vector search, persistent memory and member context, stateful workflows, tool use, orchestration, guardrails, and AI-driven personalization. Assess the existing production codebase for security vulnerabilities, scalability and performance bottlen