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+# Configuration
+
+| Meta | Value |
+|------|-------|
+| **Repo** | `xpltdco/chrysopedia` |
+| **Page** | `Configuration` |
+| **Audience** | developers, agents |
+| **Last Updated** | 2026-04-04 |
+| **Status** | current |
+
+## Overview
+
+Configuration is managed via environment variables in two `.env` files loaded by Docker Compose. The backend parses settings via `backend/config.py` (Pydantic-style with LRU caching). Frontend build-time constants are injected via Docker build args.
+
+## Environment Files
+
+| File | Purpose |
+|------|---------|
+| `.env` | Core app config (DB, Redis, LLM, auth, app settings) |
+| `.env.lightrag` | LightRAG service config (LLM model, embedding, Qdrant connection) |
+
+## Core Application (.env)
+
+### Database
+
+| Variable | Description |
+|----------|-------------|
+| `DATABASE_URL` | PostgreSQL connection string (`postgresql+asyncpg://...`) |
+
+### Redis
+
+| Variable | Description |
+|----------|-------------|
+| `REDIS_URL` | Redis connection string (`redis://chrysopedia-redis:6379/0`) |
+
+### Authentication
+
+| Variable | Description |
+|----------|-------------|
+| `APP_SECRET_KEY` | JWT signing key (HS256) |
+
+### LLM Configuration
+
+| Variable | Description |
+|----------|-------------|
+| `OPENAI_API_KEY` | API key for OpenAI-compatible endpoint |
+| `LLM_MODEL` | Primary LLM model name (DGX Sparks Qwen) |
+| `LLM_BASE_URL` | OpenAI-compatible API endpoint URL |
+
+### Application
+
+| Variable | Default | Description |
+|----------|---------|-------------|
+| `APP_VERSION` | `0.1.0` | Version string (injected into frontend) |
+| `GIT_COMMIT` | `unknown` | Git commit hash (injected into frontend) |
+| `DEBUG` | `false` | Debug mode |
+
+### Watch Directory
+
+| Variable | Description |
+|----------|-------------|
+| `WATCH_DIR` | Path to transcript JSON watch folder |
+
+## LightRAG (.env.lightrag)
+
+| Variable | Description |
+|----------|-------------|
+| `LLM_MODEL` | LLM model for LightRAG queries |
+| `EMBEDDING_MODEL` | Embedding model (`nomic-embed-text`) |
+| `QDRANT_URL` | Qdrant connection for LightRAG |
+| `WORKING_DIR` | LightRAG data directory |
+
+## Frontend Build Args
+
+Injected at Docker build time via `docker-compose.yml` build args:
+
+| Build Arg | Becomes | Purpose |
+|-----------|---------|---------|
+| `VITE_APP_VERSION` | `import.meta.env.VITE_APP_VERSION` | Version display in UI |
+| `VITE_GIT_COMMIT` | `import.meta.env.VITE_GIT_COMMIT` | Commit hash in UI |
+
+**Important:** In Dockerfile.web, the order must be `ARG` → `ENV` → `RUN npm run build`.
+
+## Docker Service Configuration
+
+### PostgreSQL
+
+- **Port:** 5433:5432 (host:container)
+- **Volume:** `chrysopedia_postgres_data`
+
+### Redis
+
+- **Port:** Internal only (6379)
+- **Persistence:** Default (RDB snapshots)
+
+### Qdrant
+
+- **Port:** Internal only (6333)
+- **Volume:** `chrysopedia_qdrant_data`
+
+### Ollama
+
+- **Port:** Internal only (11434)
+- **Volume:** `chrysopedia_ollama_data`
+- **Model:** `nomic-embed-text` (pulled on init)
+
+### LightRAG
+
+- **Port:** 9621 (localhost only on host)
+- **Volume:** `chrysopedia_lightrag_data`
+
+### Web (nginx)
+
+- **Port:** 8096:80 (host:container)
+- **Serves:** Pre-built React SPA with fallback to index.html
+
+## Pipeline Configuration
+
+LLM settings are configured per pipeline stage:
+- **Stages 1-4:** Chat model (faster, cheaper)
+- **Stage 5 (synthesis):** Thinking model (higher quality)
+- **Stage 6 (embedding):** Ollama local (`nomic-embed-text`)
+
+Prompt templates are loaded from disk (`prompts/` directory) at runtime. SHA-256 hashes are tracked for reproducibility.
+
+## Network
+
+- **Compose subnet:** 172.32.0.0/24
+- **External access:** nginx on nuc01 (10.0.0.9) → ub01:8096
+- **DNS:** AdGuard Home rewrites `chrysopedia.com` → 10.0.0.9
+
+---
+
+*See also: [[Architecture]], [[Deployment]], [[Agent-Context]]*
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