Dev Drive in Windows 11: Set It Up for Faster Builds

A Dev Drive in Windows 11 is a separate storage volume built for software development: it uses the ReFS file system instead of NTFS, and Microsoft Defender can scan it in a lighter “performance mode”. If you spend your day cloning repositories, restoring packages and running builds, moving that work onto a Dev Drive is one of the few speed improvements Windows offers that needs no new hardware.

This guide explains who it is for, what you need, the three ways to create one, what to store on it, how trust and antivirus scanning work, and how to remove it again. It is based on Microsoft’s Dev Drive documentation and applies to current Windows 11 releases (24H2 and 25H2).

Who benefits, and who does not

A Dev Drive helps when a workload touches very many small files: package managers unpacking thousands of files, compilers writing intermediate output, Git checking out large trees. Microsoft links to its own measurements in a Visual Studio blog post rather than promising a fixed gain, and the effect varies with the project.

It is not meant for general storage. Microsoft does not recommend installing applications on a Dev Drive, and photos, documents or games gain nothing from it. If you only write the occasional script, you can skip it. The same goes for PCs with little free space: a 50 GB minimum is a lot to give up on a small laptop SSD, and our guide to Windows 11 storage settings can help you find room first.

Requirements

Requirement	Microsoft’s figure
Windows version	Windows 11 build 10.0.22621.2338 or later
Memory	8 GB minimum, 16 GB recommended (ReFS uses slightly more memory than NTFS)
Free disk space	At least 50 GB (the minimum Dev Drive size)
Account	Local administrator rights
Edition	Available on all Windows editions

On a work PC your security administrator may need to enable Dev Drive through policy first. After a major Windows update, Microsoft notes that an extra restart may be needed before the option appears. To check your build, see how to check your Windows 11 version.

Step 1: open the Dev Drive setup

1. Open Settings (Windows key + I).
2. Go to System > Storage.
3. Select Advanced storage settings, then Disks & volumes.
4. Select Create dev drive.

Step 2: choose where it lives

Windows offers three options:

• Create new VHD. Windows creates a virtual hard disk file and formats it as a Dev Drive. This is the easiest choice and needs no partition changes.
• Resize an existing volume. Windows shrinks a volume to make at least 50 GB of unallocated space and builds the Dev Drive there.
• Unallocated space on disk. Shown only if you already have unallocated space.

Microsoft’s comparison is straightforward. A partition is generally a little faster because there is no virtual disk layer, but it is less flexible and resizing partitions later is more complex and risky. A VHD may be slightly slower, but it is easier to resize, move or back up. If you have never resized a partition, read our guide to partitioning a hard drive in Windows 11 and back up first.

Step 3: VHD settings

For a new VHD you choose:

• Name and location. The default location is the root of the C: drive; Microsoft recommends a folder inside your own user profile to avoid unintended sharing.
• Size. At least 50 GB.
• Format. VHDX is recommended: it supports up to 64 TB and copes better with power cuts. Plain VHD tops out at 2,040 GB.
• Disk type. Dynamically expanding (recommended) grows as you add data; fixed size takes all the space at once.

Windows then creates, attaches and formats the drive, and it appears in File Explorer with its own letter.

What to put on a Dev Drive

Microsoft lists three kinds of content:

• Source code repositories and project files.
• Package caches (npm, NuGet, pip, Cargo, Maven, Gradle, vcpkg and similar).
• Build output and intermediate files.

Moving a package cache usually means creating a folder on the Dev Drive and pointing the tool’s cache setting or environment variable at it, then moving the old cache contents across. Microsoft’s page gives the exact variable for each tool. After changing environment variables, restart open terminals or the PC so the new values apply.

Keep the tools themselves (Visual Studio, the .NET SDK, the Windows SDK) on C:. Apps installed on C: can work with files on the Dev Drive without being reinstalled. If you install tools with winget in Windows 11, leave the default install locations alone.

Trust and Microsoft Defender performance mode

A new Dev Drive is automatically marked as trusted. That flag tells Microsoft Defender to use performance mode on it: files are still scanned, but in a way that reduces the delay on file operations. Real-time protection stays fully on for every other drive. Performance mode needs the drive to be trusted and Defender real-time protection to be on.

If you move a VHD-based Dev Drive to another PC, it is treated as an ordinary volume until you mark it trusted again from an administrator terminal. Microsoft advises caution when trusting a drive at any time other than when you created it.

Microsoft also documents a way to detach antivirus filters from Dev Drives entirely, and warns in strong terms that this is a security risk. For a home or small-business PC, keep the default. Our Windows Security guide covers the rest of Defender’s settings.

Limits worth knowing

• The C: drive cannot be a Dev Drive.
• Existing volumes cannot be converted without erasing them.
• Removable drives, and VHDs stored on removable drives, cannot be Dev Drives.
• Dynamic disks are not supported.
• Files used from WSL Linux distributions do not get faster; keep those inside the Linux file system, as explained in our WSL 2 guide.
• A Dev Drive VHD stored on a BitLocker-encrypted volume is covered by that encryption.

Back up or delete a Dev Drive

Package caches can be rebuilt, so backups only need your own work. A VHD-based Dev Drive is a single file you can copy elsewhere while it is detached; a partition-based one can be backed up with File History or your usual tool.

To delete it, open Disks & volumes, select Properties next to the Dev Drive and choose Delete under Format. If it was a VHD, the file still takes up space: open Disk Management, right-click the disk (not the volume), choose Detach VHD, and then delete the file.

For more developer-focused tools built into Windows, see the Windows 11 productivity hub.