This project really should be resurrected; I'll try to find a student for this in Cambridge for the next academic cycle! I was just thinking a few days ago [1] about how a webassembly architecture for Linux brings out many of the same issues: you need to recompile apps, but then have a very flexible FFI to the outside world.

The tombl Linux-wasm [2] seems like it could be a path to upstream many of the ideas in UKML, but with a new target arch behind it so it's not just a performance boost but also a portability one. The browser demo is pretty impressive: https://linux.tombl.dev

[1] https://anil.recoil.org/notes/wasm-on-exotic-targets [2] https://github.com/tombl/linux