IIS Multi-Environment Subpath Hosting

I’m running IIS 10 on a single Windows server and need the same web application to appear under three distinct paths—/dev, /qa, and /prod—while remaining fully isolated in their configuration and runtime behaviour.

What I want to walk away with is a clean IIS setup (or deployment script) that:

• serves http://sample.com/dev, /qa and /prod from one codebase yet keeps each instance in its own app pool so database strings, integration keys and feature-flag settings never bleed across;
• lets me adjust those settings quickly through web.config transforms or any other best-practice technique you recommend;
• includes clear IIS-10-specific instructions so future updates or rollbacks stay painless.

If you have solid IIS support experience and can demonstrate how to achieve this structure—documentation plus the actual working configuration—let’s talk.