Some time ago this example used to work:

\enableregime[utf]

\usetypescript[modern-base][t2a]
\setupbodyfont[modern]

\starttext
Немного текста.
\stopbuffer

This requires cm-super package. Unfortunately after some update this
stopped working.

If someone puts me on a right way to start debugging font loading
mechanism I'll try to sort this out. Problem is that map files seem to
be loaded, fonts are installed in right places but ConTeXt doesn't try
to generate tfm. It just always uses default fonts (LM ones with ec
encoding). I've tried varous combinations (\setupencoding, fiddling with
typescripts) with no difference. Tried this on MkII, as MkIV seem to
require even more tuning.

Gour wrote:
> Hello!
>
> I was able to persuade one user to prepare ConTeXt package for NixOS
> distro, but, unfortunately, being from Russia he quickly discovered that
> he minimal example from wiki (http://wiki.contextgarden.net/Russian)
> does not work, i.e.
>
> \enableregime[utf]
> \useencoding[cyr]
>
> \definetypeface [russian]
>   [rm] [serif] [computer-modern] [default] [encoding=t2a]
>
> \setupbodyfont[russian]
> \starttext
> Мама и Папа % Some Russian characters
> \stoptext
>
>
> does transliterate Russian characters.
>
> I do not have any experience working with Cyrillic, so if anyone can
> provide minimal working example it would be very nice?
>
> I persistently claimed that "it must work!" :-)
>
>
> Sincerely,
> Gour
>
>   
> ------------------------------------------------------------------------
>
> ___________________________________________________________________________________
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>
> maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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> wiki     : http://contextgarden.net
> ___________________________________________________________________________________
>   

-- 
Best Regards,
Oleg Kolosov