Webvm: Virtual Machine for the Web

Hello again HN. Lead dev of WebVM and CTO of Leaning Technologies here. Happy to answer any question from the community.

I've heard about CheerpJ and your Flash solution too. You guys pump out a lot of pretty sophisticated web middlewares. Supposing people were fully aware of your technology, which application do you think would have the highest yield to be ported to your portfolio of middlewares?

We envision virtualization of corporate internal apps to be of the most interesting markets in the short-medium term. CheerpJ has been very successful in this segment for quite some time already. CheerpX can be seen as an alternative to Citrix, at least for some use cases.

In the longer term we plan to get unmodified Docker containers to work with CheerpX, including exposing REST APIs to the local Web app.

We have also internally speculated about a marketplace-like system to allow immediate conversion of traditional client-side apps to Web apps. This would be intended for the long tail of client software vendors that have not yet adopted Web-first distribution methods.

This is really impressive!

You mention having a "virtual block-based file system". How easily can people integrate other devices into the VM, including custom devices? For instance, if someone had a different network filesystem they wanted to use, which could be tunneled over WebSocket or WebTransport, how easily could they integrate that into this? What's the equivalent of virtio here?

It looks like the client-side bits are largely proprietary? Is CheerpX the primary thing you consider to be your competitive advantage, or is it more about all the layers you're putting on top of that for things like Flash and Java and Oracle Forms and converting local apps to web apps?

It'd be nice to be able to build atop the underlying VM and extend it for all sorts of purposes, the way KVM has been open enough to become a focal point for the modern cloud, and have just the enterprise-y bits and "convert your local app to a web app" framework running on top of that being proprietary.

We don't currently expose an API to integrate custom block devices, although it could be possible. We provide an integrated backend based on HTTP byte ranges that can work on any standard compliant HTTP server. See here for more info: https://cheerpx.io/docs/guides/File-System-support#block-dev...

CheerpX is indeed proprietary, but free-to-use for individuals and open source projects. We do want to see the community building on top of our tech. Our Flash product is build on top of CheerpX and the official Flash player plugin that needs to be licensed separately from Harman/Adobe. Java support is provided by a completely different product called CheerpJ, although lots of the ideas and parts of the JIT engines are shared with CheerpX.

At this stage we believe that keeping CheerpX proprietary serves our growth plans the best, this could of course change over time as adoption increases and we build further added-value products on top. On the other hand the WebVM integration is FOSS since it doubles as an extensive sample of what can you build with our technology.

> We don't currently expose an API to integrate custom block devices, although it could be possible.

I was thinking more about arbitrary custom devices, like custom network drivers (e.g. to connect to a server-side virtual network rather than tailscale) or custom filesystem drivers at either the block or FS layer.

> At this stage we believe that keeping CheerpX proprietary serves our growth plans the best, this could of course change over time as adoption increases and we build further added-value products on top.

I'd be very interested in chatting with you about our respective products' future plans.

> I'd be very interested in chatting with you about our respective products' future plans.

Sure, you can find me and the rest of the team on Discord: https://discord.leaningtech.com

Being able to run docker containers on the web will immediately unlock so many usecases for my work! Right now I've been trying to get a Python sentence parser to run in the browser but it requires a lot of the ecosystem (Pytorch and such). Which is not trivial to compile to WASM.

That would fit our vision for a new generation of Web apps with traditional server-side payloads running client-side, with lots of positive impacts on user privacy and operational costs.

The main difficulties right now are two:

* Most docker containers are 64-bit, while CheerpX currently only support 32-bit x86 code * Due to CORS limitations it is not currently possible to downloaded layers from repositories such as Docker Hub

The first limitation will be eventually fixed, the second one will require a specialized repository, a proxy, or co-operation from the existing repositories.

Can it be installed and run offline as a WebApp?

Not right now, WebVM/CheerpX support large disks (1GB+) to be able to run complete distributions. This an advantage of the solution, but it also means that it cannot run completely offline unless we provide a way to pre-download all this data. This does not seem a practical solution.

Fundamentally, a real VM running a real OS needs lots of data.

I was thinking of a Chrome plugin to enable this, I think plugins can make arbitrary API calls.