GPU fixes

app/Dockerfile

@@ -1,9 +1,11 @@
 ## GPU-ready base image with CUDA 12 + cuDNN 9 runtime
 # If you don't have an NVIDIA GPU or the NVIDIA Container Toolkit, this image still runs on CPU.
 # For smaller CPU-only images, you can switch back to python:3.11-slim.
-# Use a widely available CUDA + cuDNN runtime tag. If you prefer newer CUDA,
-# adjust this to a tag that exists on Docker Hub.
-FROM nvidia/cuda:12.3.2-cudnn8-runtime-ubuntu22.04
+# Base image is configurable so you can choose CPU-only or CUDA+cuDNN runtime.
+# Default to Python slim for maximum compatibility; override via build-arg
+# BASE_IMAGE (or docker-compose build args) to use an NVIDIA CUDA runtime.
+ARG BASE_IMAGE=python:3.11-slim
+FROM ${BASE_IMAGE}
 
 # Keep python fast/quiet and pip lean
 ENV PYTHONDONTWRITEBYTECODE=1 \