Mapping drive letters to give Windows AI coding agents isolated workspaces

On October 24, 2026, a developer published a walkthrough on DEV Community showing how to set up a workspace for AI coding agents on Windows. The approach maps a local folder to a drive letter, and mounts remote or WebDAV storage as a drive letter as well, so the agent reads and writes to what looks like an ordinary disk. The author contrasts this with Docker volumes, noting that Docker requires a running container, path translation, networking, and image management, while a mapped drive letter appears to Windows as a real drive that every tool can use with no overhead. Two specific tools are cited: subst.scsoi.com maps a local folder to a drive letter for local agent workspaces, and drive.scsoi.com mounts storage as a drive letter for remote or WebDAV agent workspaces. The agent simply sees a normal drive and can write to it freely.

Eight minutes later, at 16:03 the same day, another DEV Community post shifted the emphasis from convenience to isolation. It warns that an AI coding agent can read your .ssh folder, edit your hosts file, or delete your entire C: drive if something goes wrong, and proposes mapping the agent's workspace to its own dedicated drive letter as the fix. The author claims this needs a one-time setup and keeps running, with the agent seeing only a normal drive, writing to it happily, and unable to see anything outside that drive. No Docker Desktop and no VM are required, just Windows' built-in drive mapping. Both posts reference subst.scsoi.com and drive.scsoi.com for the mapping step itself. So far the practice remains a developer-shared technique on DEV Community, without any broader vendor or platform adoption being reported.