\setuppagenumber[state=stop]
\nopdfcompression

\startuniqueMPgraphic{foo:special}
begingroup
    save p; path p;
    p := unitsquare xyscaled(2cm,2cm);

    linear_shade(p,1,red,green);

    interim linejoin:= rounded; interim linecap:= rounded;
    draw p withpen pencircle scaled 10;
endgroup;
\stopuniqueMPgraphic

\startuniqueMPgraphic{foo:nospecial}
begingroup
    save p; path p;
    p := unitsquare xyscaled(2cm,2cm);

%    linear_shade(p,1,red,green);
    interim linejoin:= rounded; interim linecap:= rounded;
    draw p withpen pencircle scaled 10;
endgroup;
\stopuniqueMPgraphic


\starttext
\uniqueMPgraphic{foo:special}

\uniqueMPgraphic{foo:nospecial}


\stoptext