For Russian I have:

\setuplanguage[ru][patterns={ru}]\mainlanguage[ru]
\definefallbackfamily
  [archimate]
  [ss]
  [Helvetica]
  [preset=range:cyrillic,
   tf=style:light,
   it=style:lightoblique,
   bf=style:regular,
   bi=style:oblique,
   force=yes,
 rscale=1.0]
\definefontfamily [archimate] [ss] [Optima]
\setupbodyfont[archimate]

I can’t find out from ConTeXtgarden what code I must use for modern Greek (‘el’?) and what range I must use for Greek characters (I guess ‘greekandcoptic’ which I’ve seen mentioned somewhere).

Correct?

Gerben Wierda (LinkedIn <https://www.linkedin.com/in/gerbenwierda>)
R&A IT Strategy <https://ea.rna.nl/> (main site)
Book: Chess and the Art of Enterprise Architecture <https://ea.rna.nl/the-book/>
Book: Mastering ArchiMate <https://ea.rna.nl/the-book-edition-iii/>