| Layer | Technology |
|---|---|
| Backend API | FastAPI Mangum Python 3.12 uv |
| Frontend | Next.js TypeScript Tailwind v4 lucide-react |
| Vector Storage | PostgreSQL 16 pgvector HNSW index AWS RDS (shared db-v2) |
| Engagement DB | PostgreSQL (isolated) SQLAlchemy async JSONB turns/extras |
| Embeddings | OpenAI text-embedding-3-small 1536-dim |
| LLM (swappable) | OpenAI gpt-4o-mini Anthropic Claude |
| Document Processing | pdfplumber BeautifulSoup4 python-docx fpdf2 |
| Shared Library | aiplatform — loaders, chunker, embedder, vector store, LLM providers, settings |
| AWS Infra | Lambda (container) API Gateway Cognito S3 CloudFront Route 53 ACM |
| Quality | eval.py — 24 golden cases · rule-based checks · LLM-as-judge (gpt-4o) · 78 tests green |