> ## Documentation Index > Fetch the complete documentation index at: https://documentation.rebase.energy/llms.txt > Use this file to discover all available pages before exploring further. # Apps > Serve data apps {/* Inspired by: https://www.numerous.com/docs https://modal.com/docs/examples/serve_streamlit */} ```python from pydantic import BaseModel from fastapi.responses import HTMLResponse from modal import Image, App, web_endpoint image = Image.debian_slim().pip_install("boto3") app = App(image=image) # Note: prior to April 2024, "app" was called "stub" class Item(BaseModel): name: str qty: int = 42 @app.function() @web_endpoint(method="POST") def f(item: Item): import boto3 # do things with boto3... return HTMLResponse(f"Hello, {item.name}!") ```