TLDR: Both WebContainers and Nodebox are promising and interesting tools. However, these tools being closed source is somewhat problematic and both come with some important technical limitations.
Whilst super interesting and offering a cool developer experience, these systems aren’t practical enough to use in commercial projects yet without investing significant time into them.
Both WebContainers and Nodebox have been opened up to some degree, allowing developers to build their own applications and integrations. However, it is important to be mindful of vendor lock-in and to create experiences that are not directly tied to one sandboxing technology. While this is possible today, it requires implementing a lot of functionality from scratch, which incurs a high maintenance overhead.
Both tools make use of telemetry and, on occasion, load remote assets under the hood, so have the potential to leak sensitive work you’re experimenting with (that you shouldn’t due to licensing, confidentiality, NDAs, etc…). Also, if you’re using an ad-blocker then this could potentially impact your experience, as well as the use of third-party cookies coupled with local storage.
It is important to remember that whilst free for use on open source projects, both tools are proprietary systems run by for-profit companies. This is not a bad thing but you really should look into the licensing and usage aspects of both if you’re considering developing any type of commercial application.
Overall, we seem to have a very promising future despite their caveats. It is of course worth noting that having a healthy competition between the two is great for the ecosystem. Let’s hope for native open source implementations in the future.