I'm relatively new to AWS AppRunner, and I'm trying to deploy a simple FastAPI endpoint to perform some tests. Here is the main.py file : from fastapi import FastAPI import uvicorn from pydantic import BaseModel import numpy as np app = FastAPI() class InputNumber(BaseModel): value: float @app.post("/sqrt") async def compute_sqrt(input_data: InputNumber): result = np.sqrt(input_data.value) return {"result": float(result)} if __name__ == '__main__': uvicorn.run(app, port=8080, host='0.0.0.0') With this code, I have of course a requirements.txt file : fastapi uvicorn[standard] numpy pydantic At first, I tried to deploy it with Python 3, and the following commands : build command : pip install -r requirements.txt start command : python main.py Everything worked perfectly fine, and I tried to deploy it with Python 3.11 with the following commands : build command : pip3 install -r requirements.txt start command : python3 main.py The build is working fine, but I'm getting an unexpected error when the deployment starts: ModuleNotFoundError: No module named 'fastapi' The build was correctly performed (every lib was downloaded as seen in the logs), and the same error occurs when adding a version to the libs in the requirements.txt file. I don't have docker Thanks in advance ! Continue reading...