WSL vs Docker for GUI Dev in VS Code

A concise comparison between the differences and advantages of WSL and Docker containers, assuming a more advanced setup using custom development containers.

Goal:
To provide an easily installable, isolated development environment with tools and project templates to build GUI applications that run on the Windows host. Visual Studio Code is used as the development IDE.

Similarities & Requirements

Both WSL and Docker containers can display GUI applications on the Windows host.

1. WSL
   • Requires Windows 11
   • Requires the WSL extension in Visual Studio Code (ms-vscode-remote.remote-wsl) — optional but recommended (see ‘Usage’)
   • Uses WSLg, a Wayland-based X server built into Windows 11, to render GUI apps on the host
2. Docker
   • Works on Windows 10 or newer
   • Requires the Dev Containers extension in VS Code (ms-vscode-remote.remote-containers)
   • Requires XLaunch (VcXsrv) installed on the Windows host to handle X11 display¹ This ensures the received X11 protocol information on the host is handled properly.
   • The dockerfile requires a defined variable Display: ENV DISPLAY=host.docker.internal:0
   • In your Docker Compose file, define the environment variable as follows (to make sure X11 protocol information is send to the host)

  environment:        
            - DISPLAY=host.docker.internal:0    # THIS relays the linux output to vcxsrv(Xlaunch)

Usage

This describes how to use the different approaches in Visual Studio Code

1. WSL
   You have two ways to develop with WSL in Visual Studio Code:
   
   
   • Install and run VS Code inside the WSL environment²
     This launches the full VS Code IDE from within the WSL environment using WSLg. This is not the recommended way, but may be useful when developing low-level Linux system software.
     
     
   • Use the VS Code WSL extension (Recommended ✨)
     Start VS Code on Windows and use the WSL extension to open the project inside the WSL environment. When you run your GUI app, WSLg handles display output to the Windows host seamlessly.
2. Docker
   The standard and recommended ✨ method is to:
   • Start VS Code on the Windows host
   • Use the Dev Containers extension to open a Docker container as the development environment

Running GUI apps from within the container will forward display output via X11 to the Windows host using XLaunch.

Warning While technically possible, running VS Code from inside a Docker container is uncommon and poorly supported

Advantages & performance

Docker with X11 is generally the most responsive option:

• Works with Windows 10 and newer
• GUI apps launch faster and feel more responsive
• Uses direct X11 communication to XLaunch, reducing latency
• Runs in an isolated network environment
• Security: Docker offers more isolation and is generally more secure

WSLg, while integrated and simpler to set up, has:

• Noticeable startup delays (e.g. launching gedit may take 5+ seconds)
• Additional overhead due to Wayland → Weston → FreeRDP → Windows pipeline
• More components involved, which can introduce lag for certain GUI app
• Runs in a more direct (NAT-like) network environment, with less isolation

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Footnotes

1. or equivalent X11 program
2. strictly speaking, WSL is not a container system like Docker. WSL is a lightweight VM hosting a Linux distribution, not an OCI-compliant container

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