Getting PHP Composer package manager working with WordPress seems harder than getting it work in Wasm. Next hopeful attempt with https://github.com/BrianHenryIE/strauss.

@sander Thank's, but I think this covers a setup for a single WP site handling it's deps with global Composer setup. I've managed with something similar in site projects.

Actually what I'm banging head against is trying to pack Composer deps into a installable plugin (or theme) and the "scoping" / "renamespacing".