What’s the Best Way to Safely Run Python and C# Code in a Web App?

I'm building a website where users can execute small Python and C# snippets, but I need to measure the runtime of these processes. I found out that platforms like Netlify and Vercel don't support running Docker or custom runtimes, which leads me to seek a backend solution that can create isolated containers for execution. I'm a bit confused about the architecture I should use. Here are my options: - Should I host the frontend and backend separately (frontend on Netlify/Vercel and backend on a different platform like Render or AWS)? - Or would it make more sense to host both the frontend and backend on Render as two services? - Is there another approach that might be better? The backend needs to: - Run Docker containers - Sandbox code submitted by users - Enforce execution time limits - Return both stdout/stderr and execution time If anyone with experience in online coding platforms, judge systems, or safe execution environments could shed some light on the simplest and cleanest setup, that would be incredibly helpful!