% engine=luatex 
\noheaderandfooterlines

\starttext

 \definefontfeature
   [arabic]
   [analyze=yes, clig=yes, curs=yes, dlig=yes,
    fina=yes, init=yes, isol=yes, kern=yes,
    language=dflt, liga=yes, mark=yes, medi=yes,
    mkmk=yes, mode=node, rlig=yes, script=arab]

\font \Arabic = ScheherazadeRegOT*arabic at 24pt
%\font \Arabic = ae_AlMohanad*arabic at 24pt

\pardir TRT \textdir TRT

\Arabic
خ‌ج‌ح
خ‍ ج‍ ح‍
\stoptext