webvm

WebVM

This repository hosts the source code for https://webvm.io, a Linux virtual machine that runs in your browser.

Try out the new Alpine / Xorg / i3 graphical environment: https://webvm.io/alpine.html

WebVM is a server-less virtual environment running fully client-side in HTML5/WebAssembly. It's designed to be Linux ABI-compatible. It runs an unmodified Debian distribution including many native development toolchains.

WebVM is powered by the CheerpX virtualization engine, and enables safe, sandboxed client-side execution of x86 binaries on any browser. CheerpX includes an x86-to-WebAssembly JIT compiler, a virtual block-based file system, and a Linux syscall emulator.

Enable networking

Modern browsers do not provide APIs to directly use TCP or UDP. WebVM provides networking support by integrating with Tailscale, a VPN network that supports WebSockets as a transport layer.

• Open the "Networking" panel from the side-bar
• Click "Connect to Tailscale" from the panel
• Log in to Tailscale (create an account if you don't have one)
• Click "Connect" when prompted by Tailscale
• If you are unfamiliar with Tailscale or would like additional information see WebVM and Tailscale.

Fork, deploy, customize

• Fork the repository.
• Enable Github pages in settings.
  • Click on Settings.
  • Go to the Pages section.
  • Select Github Actions as the source.
    • If you are using a custom domain, ensure Enforce HTTPS is enabled.
• Run the workflow.
  • Click on Actions.
  • Accept the prompt. This is required only once to enable Actions for your fork.
  • Click on the workflow named Deploy.
  • Click Run workflow and then once more Run workflow in the menu.
• After a few seconds a new Deploy workflow will start, click on it to see details.
• After the workflow completes, which takes a few minutes, it will show the URL below the deploy_to_github_pages job.

You can now customize dockerfiles/debian_mini to suit your needs, or make a new Dockerfile from scratch. Use the Path to Dockerfile workflow parameter to select it.

Run WebVM locally with a custom Debian mini disk image

1. Clone the WebVM Repository

   git clone https://github.com/leaningtech/webvm.git
   cd webvm
   

2. Download the Debian mini Ext2 image

   Run the following command to download the Debian mini Ext2 image:

   wget "https://github.com/leaningtech/webvm/releases/download/ext2_image/debian_mini_20230519_5022088024.ext2"
   

   (*You can also build your own disk image by selecting the "Upload GitHub release" workflow option*)

3. Update the configuration file

   Edit config_public_terminal.js to reference your local disk image:

• Replace:

  "wss://disks.webvm.io/debian_large_20230522_5044875331.ext2"

  With:

  "/disk-images/debian_mini_20230519_5022088024.ext2"

  (Use an absolute or relative URL pointing to the disk image location.)

• Replace "cloud" with the correct disk image type: "bytes"

1. Build WebVM

   Run the following commands to install dependencies and build WebVM:

   npm install
   npm run build
   

   The output will be placed in the build directory.

2. Configure Nginx

• Create a directory for the disk image:

  mkdir disk-images
  mv debian_mini_20230519_5022088024.ext2 disk-images/
  

• Modify your nginx.conf file to serve the disk image. Add the following location block:

  location /disk-images/ {
      root .;
      autoindex on;
  }
  

1. Start Nginx

   Run the following command to start Nginx:

   nginx -p . -c nginx.conf
   

   Nginx will automatically serve the build directory.

2. Access WebVM

   Open a browser and visit: http://127.0.0.1:8081.

   Enjoy your local WebVM!

Example customization: Python3 REPL

The Deploy workflow takes into account the CMD specified in the Dockerfile. To build a REPL you can simply apply this patch and deploy.

diff --git a/dockerfiles/debian_mini b/dockerfiles/debian_mini
index 2878332..1f3103a 100644
--- a/dockerfiles/debian_mini
+++ b/dockerfiles/debian_mini
@@ -15,4 +15,4 @@ WORKDIR /home/user/
 # We set env, as this gets extracted by Webvm. This is optional.
 ENV HOME="/home/user" TERM="xterm" USER="user" SHELL="/bin/bash" EDITOR="vim" LANG="en_US.UTF-8" LC_ALL="C"
 RUN echo 'root:password' | chpasswd
-CMD [ "/bin/bash" ]
+CMD [ "/usr/bin/python3" ]

Bugs and Issues

Please use Issues to report any bug. Or come to say hello / share your feedback on Discord.

More links

• WebVM: server-less x86 virtual machines in the browser
• WebVM: Linux Virtualization in WebAssembly with Full Networking via Tailscale
• Mini.WebVM: Your own Linux box from Dockerfile, virtualized in the browser via WebAssembly
• Reference GitHub Pages deployment: Mini.WebVM
• Crafting the Impossible: X86 Virtualization in the Browser with WebAssembly Talk at JsNation 2022

Thanks to...

This project depends on:

• CheerpX, made by Leaning Technologies for x86 virtualization and Linux emulation
• xterm.js, https://xtermjs.org/, for providing the Web-based terminal emulator
• Tailscale, for the networking component
• lwIP, for the TCP/IP stack, compiled for the Web via Cheerp

Versioning

WebVM depends on the CheerpX x86-to-WebAssembly virtualization technology, which is included in the project via NPM.

The NPM package is updated on every release.

Every build is immutable, if a specific version works well for you today, it will keep working forever.

License

WebVM is released under the Apache License, Version 2.0.

You are welcome to use, modify, and redistribute the contents of this repository.

The public CheerpX deployment is provided as-is and is free to use for technological exploration, testing and use by individuals. Any other use by organizations, including non-profit, academia and the public sector, requires a license. Downloading a CheerpX build for the purpose of hosting it elsewhere is not permitted without a commercial license.

Read more about CheerpX licensing

If you want to build a product on top of CheerpX/WebVM, please get in touch: sales@leaningtech.com