How to Create and Use a Dev Drive in Windows 11 for Faster Development

Dev Drive is a dedicated storage volume type introduced in Windows 11 that is specifically optimised for developer workloads. Built on the Resilient File System (ReFS), a Dev Drive provides significantly faster file I/O performance for operations that developers perform constantly — cloning repositories, building projects, running package managers, and executing file-heavy compilation tasks.

If you work with large codebases, use tools like npm, NuGet, pip, cargo or Maven, or regularly build projects from source, moving your project files and package caches to a Dev Drive can noticeably reduce build times and improve overall development workflow speed.

Why Dev Drive Exists

Traditional NTFS volumes in Windows are general-purpose file systems designed to handle everything from system files to user documents to database storage. While NTFS is reliable, its design involves significant overhead for operations like file metadata updates, journaling, and security descriptor checks — all of which slow down the rapid, repeated small-file operations that characterise developer workflows.

Dev Drive addresses this by using ReFS with a specialised performance mode that reduces file system overhead. It also integrates with Microsoft Defender Antivirus to apply a more targeted scanning approach, avoiding the redundant real-time scans of build artefacts that can cripple compilation performance.

Requirements for Creating a Dev Drive

• Windows version: Windows 11, version 23H2 or later.
• RAM: At least 8 GB of physical memory (16 GB recommended).
• Disk space: At least 50 GB of free space for the Dev Drive volume.
• Administrator access: You need administrator privileges to create a Dev Drive.

How to Create a Dev Drive

1. Open Settings (press Win + I).
2. Navigate to System > Storage.
3. Expand Advanced storage settings.
4. Click Disks & volumes.
5. Click Create Dev Drive.

You will be presented with three options for creating the volume:

Option 1: Create a New Virtual Hard Disk (VHD)

This creates a virtual disk file on your existing drive. The VHD appears as a separate volume in File Explorer. This is the simplest option and does not require repartitioning your physical disk.

1. Select Create new VHD.
2. Choose a name, location and size for the virtual disk (minimum 50 GB).
3. Click Create.

Windows creates a .vhdx file, formats it with ReFS, and mounts it as a new drive letter.

Option 2: Resize an Existing Volume

If you have a large partition with available free space, you can shrink it and use the unallocated space for a Dev Drive.

1. Select Resize an existing volume.
2. Choose the volume to shrink.
3. Specify how much space to allocate to the Dev Drive.
4. Click Create.

Option 3: Use Unallocated Space

If you already have unallocated space on a physical disk (from a previous partition deletion, for example), you can use it directly.

1. Select Use unallocated space on an existing disk.
2. Choose the disk and unallocated region.
3. Click Create.

After creation, the Dev Drive appears in File Explorer with its assigned drive letter, ready to use.

What to Store on a Dev Drive

For maximum benefit, move the following to your Dev Drive:

Source Code and Repositories

Clone your Git repositories directly onto the Dev Drive. The faster file system operations reduce the time for git clone, git checkout, git status, and git diff, particularly for large repositories with thousands of files.

Package Caches

Package managers like npm, NuGet, pip, Maven and cargo store downloaded packages in local caches. Moving these caches to the Dev Drive speeds up package restoration. To redirect caches, set the appropriate environment variables:

• npm: npm config set cache D:\DevDrive\npm-cache
• NuGet: Set the NUGET_PACKAGES environment variable to D:\DevDrive\nuget-packages.
• pip: Set the PIP_CACHE_DIR environment variable to D:\DevDrive\pip-cache.
• cargo: Set the CARGO_HOME environment variable to D:\DevDrive\cargo.

Replace D:\DevDrive\ with your actual Dev Drive path.

Build Output Directories

Configure your build tools to output compiled binaries, object files, and intermediate artefacts to the Dev Drive. This is where the ReFS performance gains are most noticeable, as build systems perform thousands of small file writes during compilation.

Microsoft Defender Performance Mode

Dev Drive integrates with Microsoft Defender Antivirus through a special performance mode. When enabled, Defender uses a more efficient scanning approach for files on the Dev Drive:

• Build artefacts and temporary files generated during compilation are scanned asynchronously rather than synchronously.
• Known safe operations (like npm installing packages from a trusted registry) receive reduced scanning overhead.
• Full security protection is maintained — performance mode does not disable antivirus, it optimises when and how scans occur.

Performance mode is enabled by default for Dev Drives. You can verify this in Windows Security > Virus & threat protection > Manage settings > Dev Drive protection.

Performance Gains

Microsoft’s internal benchmarks show significant performance improvements for common developer operations on Dev Drive compared to standard NTFS volumes:

• Build times: Up to 30% faster for large C++ and C# projects.
• Package restore: npm install and NuGet restore operations complete significantly faster due to reduced file I/O overhead.
• Git operations: Clone, checkout, and status commands are faster, particularly for repositories with many small files.

The actual improvement depends on your specific workload, disk hardware (SSD vs HDD), project size, and whether your current bottleneck is file I/O or CPU-bound compilation.

Important Limitations

• ReFS only: Dev Drive volumes use ReFS, not NTFS. Some older tools or backup software may not support ReFS.
• Not for system files: Do not install Windows, applications, or drivers on a Dev Drive. It is designed exclusively for developer project files, caches, and build output.
• Minimum size: The volume must be at least 50 GB.
• No BitLocker by default: While you can enable BitLocker on a Dev Drive, it may reduce some of the performance benefits.

How to Delete a Dev Drive

If you no longer need the Dev Drive:

1. Move any files you want to keep to another drive.
2. Open Settings > System > Storage > Advanced storage settings > Disks & volumes.
3. Select the Dev Drive volume.
4. Click Delete.

If the Dev Drive was created as a VHD, you can also simply delete the .vhdx file from your disk.

Dev Drive is a practical performance tool for anyone who develops software on Windows 11. By isolating developer workloads on a ReFS volume with optimised Defender integration, it removes two of the biggest file I/O bottlenecks that slow down builds and development tools — without requiring any changes to your code or development workflow.