Add Dockerfile and HF Spaces deployment config

- Multi-stage Docker build (Node frontend + Python backend)
- Backend serves built frontend as static files in production
- HF Spaces metadata in README frontmatter
- CONCENTRATE_API_KEY read from env (set as HF Space secret)

Made-with: Cursor

Dockerfile

@@ -0,0 +1,26 @@
+# Stage 1: Build the React frontend
+FROM node:20-slim AS frontend-build
+WORKDIR /app/frontend
+COPY frontend/package.json frontend/package-lock.json ./
+RUN npm ci
+COPY frontend/ ./
+RUN npm run build
+
+# Stage 2: Python backend + built frontend
+FROM python:3.11-slim
+WORKDIR /app
+
+RUN useradd -m -u 1000 appuser
+
+COPY backend/requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY backend/main.py .
+COPY --from=frontend-build /app/frontend/dist ./static/
+
+RUN chown -R appuser:appuser /app
+USER appuser
+
+EXPOSE 7860
+
+CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "7860"]

README.md

@@ -1,3 +1,12 @@
+---
+title: LLM Arena
+emoji: ⚔️
+colorFrom: indigo
+colorTo: purple
+sdk: docker
+app_port: 7860
+---
+
 # LLM Arena
 
 Side-by-side LLM comparison app powered by [Concentrate AI](https://concentrate.ai). Pick any two models from 70+ providers, send the same prompt, and watch both responses stream in real-time with latency, token, and cost stats.

backend/main.py

@@ -1,6 +1,7 @@
 import io
 import json
 import os
+import pathlib
 import time
 from typing import Optional
 
@@ -10,7 +11,8 @@ from docx import Document as DocxDocument
 from dotenv import load_dotenv
 from fastapi import FastAPI, HTTPException, UploadFile
 from fastapi.middleware.cors import CORSMiddleware
-from fastapi.responses import StreamingResponse
+from fastapi.responses import FileResponse, StreamingResponse
+from fastapi.staticfiles import StaticFiles
 from pydantic import BaseModel, Field
 
 load_dotenv()
@@ -22,7 +24,7 @@ app = FastAPI(title="LLM Arena Backend")
 
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=["http://localhost:5173", "http://127.0.0.1:5173"],
+    allow_origins=["*"],
     allow_credentials=True,
     allow_methods=["*"],
     allow_headers=["*"],
@@ -256,3 +258,19 @@ async def stream_response(req: StreamRequest):
 @app.get("/api/health")
 async def health():
     return {"status": "ok"}
+
+
+# ── Static file serving (production / HF Spaces) ─────────────────────────────
+
+STATIC_DIR = pathlib.Path(__file__).resolve().parent / "static"
+
+if STATIC_DIR.is_dir():
+    app.mount("/assets", StaticFiles(directory=STATIC_DIR / "assets"), name="assets")
+
+    @app.get("/{full_path:path}")
+    async def serve_spa(full_path: str):
+        """Serve the React SPA for any non-API route."""
+        file_path = STATIC_DIR / full_path
+        if file_path.is_file():
+            return FileResponse(file_path)
+        return FileResponse(STATIC_DIR / "index.html")