% For Thomas Schmitz.
% Deal with subscribed iotas
\installfontfeature[otf][grbl]
\installfontfeature[otf][grb2]

\definefontfeature
   [greek-babel]
   [mode=node,language=dflt,script=latn,
    grbl=yes,grb2=yes,featurefile=greek-babel-extended.fea]

\font\bosphoros=name:BosporosU*greek-babel at 20pt

\starttext

\catcode`\~=11
\catcode`\|=11

\bosphoros
a| h| w|

\stoptext