If this worked properly, I'd find it incredibly useful. It'd give me a Posix command-line environment inside the browser, with all the commands running locally,

If this worked properly, I'd find it incredibly useful. It'd give me a Posix command-line environment inside the browser, with all the commands running locally, backed by a file system on cloud storage somewhere, which would work anywhere, regardless of what computer I was currently working on. I've been wanting something like this for ages (and have had a few ideas along those lines myself)... The description of the technology glosses over all the really difficult bits, however, like how they turn compiled C into runnable Javascript. Emscripten? An interpreter? Gods help them, they're not using Clue, are they? How much overhead is there in executing the compiled code in chunks so that they can simulating blocking RPCs (for system calls)? Do they have a plan for threads? (I don't believe web workers support any kind of shared-memory threading.) (later) I found a demo here: https://unix.bpowers.net/ https://unix.bpowers.net/ Inspecting the code shows lots of Emscripten stuff.