I've made a significant step today in making available the first cut of my closure scheme. There is a new blog post on
www.mirandabanda.org/cogblog about the closure bytecodes which at the end includes a pointer to the bootstrap @
www.mirandabanda.org/files/Cog/Closures0808/Bootstrap/. The bootstrap has been tested on internal Qwaq images, and on Croquet 1.0 and Squeak 3.9. I'd love to hear of other ports, e.g. to 3.10 and to Spoon. I'm interested in bug reports (I haven't yet tested eToys) and code reviews and tying up loose ends (for example I broke decompile with temp names and haven't fixed it).
Thanks and enjoy.