Senior AI-Assisted Full-Stack Engineer (Stealth Startup)

Role Overview We are an early-stage wellness tech startup operating in strict stealth mode. We are seeking a highly capable, autonomous Senior Full-Stack Software Engineer to own the deployment, security hardening, and pipeline integration of our core digital engine. You will be taking an existing, highly structured, clean application repository (exported production code) and transitioning it safely into our private cloud infrastructure. This role requires an expert engineer who knows how to leverage modern AI coding assistants to move with extreme velocity, balancing rapid execution with enterprise-grade data security. 🛠 Core Responsibilities Infrastructure & Deployment: Deploy our exported full-stack application code cleanly onto a private, password-masked environment on Fly.io. Database Architecture: Establish and optimize a secure cloud database (MongoDB) to log high-value consumer metadata text records efficiently. Private AI Pipeline Integration: Wire the application’s core backend routes to premium enterprise LLM endpoints (via OpenAI Developer API / Google Vertex AI) ensuring 100% private data handling. Security Hardening (Defense-in-Depth): Architect absolute isolation for our system by implementing: AES-256 field-level encryption for database storage. Virtual Private Cloud (VPC) mapping to isolate the database from the public internet. Dual-LLM asynchronous verification loops built natively into server routes to prevent prompt injection and security jailbreaks. Zero-Data Retention (ZDR) API execution pipelines. 💻 Technical Requirements & Stack Backend Expertise: Advanced knowledge of server environment management, custom API wrapper design, and secure routing pipelines. Cloud & Database Infrastructure: Proven hands-on experience running optimized environments on Fly.io (or AWS/GCP) paired with MongoDB or similar scalable document databases. AI Engine Engineering: Deep familiarity with integrating structured developer APIs (OpenAI/Anthropic) and handling metered token volume budgets efficiently. Modern Workflows: Extensive experience using modern AI coding assistants (e.g., Cursor, Claude Dev, GitHub Copilot) to build, refactor, and deploy code single-handedly at high velocity. Security Literacy: Clear understanding of cryptographic key rotation, TLS 1.3 parameters, and modern AI system vulnerabilities (prompt injection filtering). 🎯 What We Are Looking For in You The Blueprint Reader: You can open a clean, exported full-stack repository you didn't write yourself, map its logic instantly, and deploy it onto independent servers without hand-holding. Absolute Individual Discretion: You are comfortable working under a strict Mutual Non-Disclosure Agreement (NDA) and understand the critical importance of keeping codebases entirely hidden from public repositories or search indices. The Execution Machine: You prefer small, decisive, hyper-lean environments where you deal directly with the founder and see your clean architectural choices running live in days, not months.