It's disregarded because, as far as I understand, migrating the software from elisp to guile would be daunting
I thought they weren't modifying the code itself, but running it under an Elisp compiler made in Guile. This caused a bunch of performance issues, though.
Of course, I'm unfamiliar with the project or development behind it, so I don't really know how it works.
AFAIK it isn't. The latest update is from 2015 and I have no idea what Robin is up to these days.
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