Senior Full-Stack Engineer, AI/RAG Systems (Contract)

** Please do not contact us outside of Upwork. All applications and communications must be submitted through Upwork’s standard application process. Thank you. ** About StrongAfter Mission StrongAfter is a nonprofit dedicated to making healing safer, more accessible, and less stigmatized for men who have experienced unwanted or abusive sexual experiences, as well as those who support them. Organization Highlights - Trauma-informed, evidence-based approach. - Expert collaboration with survivors, clinicians, advocates, nonprofit leaders, and technology specialists. - Serves underserved communities including veterans, military personnel, BIPOC men, justice-involved men, and transitional-age young men. - Maintains both the OSWALT platform and an expert-vetted Resource Hub. About OSWALT Purpose OSWALT is StrongAfter's AI assistant and content engine designed to provide trustworthy, trauma-informed information sourced exclusively from a curated knowledge library. Key Characteristics - Retrieval-Augmented Generation (RAG) - Grounded, cited responses - No open-web generation - Predictable and reviewable AI behavior - Supports—but never replaces—professional care and crisis services - Currently in beta refinement The Opportunity This is a high-ownership engineering role responsible for improving: - Product reliability - Answer quality - Maintainability - User experience The engineer collaborates with product leadership, therapists, subject-matter experts, and testers while producing reviewable engineering artifacts and measurable evaluation criteria. Primary Responsibilities Engineering - Own the Python/FastAPI backend. - Maintain the Angular/TypeScript frontend. - Deliver production-ready features end-to-end. AI Engineering - Utilize AI coding agents across design, coding, testing, documentation, and analysis. - Validate and review every AI-generated change before release. Product Collaboration - Refine requirements. - Define acceptance criteria. - Estimate and prioritize work. - Communicate dependencies and tradeoffs. Quality & Evaluation - Convert stakeholder feedback into reproducible test cases. - Improve retrieval, reranking, grounding, and embeddings. - Maintain evaluation datasets and knowledge infrastructure. Operations - Manage deployments in GCP. - Support containerized infrastructure. - Maintain observability, privacy, and security. Documentation - Produce concise technical documentation, including issues, plans, tests, runbooks, release notes, and decision records. Required Qualifications Technical Skills - Python - FastAPI (or equivalent) - TypeScript - Angular - Docker - Linux - CI/CD - Cloud Infrastructure AI & RAG Experience - Embeddings - Retrieval - Reranking - Grounding - Evaluation Methodologies Professional Strengths - Senior Engineering Judgment - AI-Assisted Development - Testing & Quality Assurance - Requirements Analysis - Technical Documentation - Problem Solving - Critical Thinking - Stakeholder Management - Cross-Functional Collaboration - Security & Privacy Awareness - Technical Communication Preferred Experience Experience with any of the following is beneficial but not required: - Google Cloud Platform (GCP) - NVIDIA L4 GPU Infrastructure - vLLM / Model Serving - Neo4j / Graph Databases - Vector Retrieval Systems - RAG Optimization - Safety-Sensitive AI - Mental Health Technology - Nonprofit Technology - Justice / Humanitarian Technology Working Model Cross-Functional Collaboration Work closely with: - Product Owner - Program Manager - Therapists - Subject-Matter Experts - Product Testers Engineering Philosophy - Reviewable artifacts over undocumented decisions. - Human accountability for all shipped work. - Appropriate documentation proportional to risk. - Strong emphasis on safety, privacy, and grounding. Contract Details To Be Completed - Engagement: Six-month contract (renewable) - Rate - Weekly Hours - Time-Zone Overlap - Remote / Location Expectations - Start Date - On-Call Expectations Why Join StrongAfter This role offers the opportunity to build trustworthy AI technology that supports people during deeply personal and difficult experiences while contributing to a mission-driven nonprofit committed to thoughtful, safe, and high-quality engineering.