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+# Development & Deployment Guide
+
+## Quick Start (Local Development)
+
+### Prerequisites
+- Python 3.10
+- ViennaRNA installed (`brew install brewsci/bio/viennarna` on macOS)
+- Git LFS installed (`brew install git-lfs`)
+
+### First-time Setup
+```bash
+git lfs install
+git lfs pull
+python3.10 -m venv venv310
+source venv310/bin/activate
+pip install -r webapp/requirements.txt
+```
+
+### Run Locally
+```bash
+source venv310/bin/activate
+python -m uvicorn webapp.app.main:app --port 7860 --reload
+```
+
+Visit: http://localhost:7860
+
+## Docker Development
+
+### Build & Run
+```bash
+docker compose up --build
+```
+
+### Production-like Run
+```bash
+docker compose -f docker-compose.prod.yml up
+```
+
+## Deployment to Hugging Face Spaces
+
+### Automatic (CI/CD) - Recommended
+Push to `main` branch triggers automatic deployment:
+```bash
+git push origin main
+```
+
+The GitHub Action will:
+1. Run tests
+2. Push to HF Spaces (https://huggingface.co/spaces/sachin1801/splicing-predictor)
+
+### Manual Deployment
+```bash
+git push hf main
+```
+
+### Required Secrets
+- `HF_TOKEN` - Hugging Face access token with write permissions
+
+## Troubleshooting
+
+### "file signature not found" error
+Run: `git lfs pull`
+
+### Port mismatch (Shiny apps show "connection failed")
+Use port 7860: `python -m uvicorn webapp.app.main:app --port 7860`
+
+### Database corruption
+Delete and restart: `rm webapp/splicing.db`