\setuppapersize     [A6][A3]
\setuparranging     [2*4,doublesided]
\setuppagenumbering [alternative=doublesided]
\setuplayout        [margin=0pt,width=fit]
\setupbackgrounds   [text][text][background=screen]
\setupcolors        [state=start]
\setuplayout        [location=middle,marking=color]
\setuptolerance     [tolerant]
\setupbodyfont      [lbr,7pt]

\starttext 
  \dorecurse{30}{\input tufte \par \input knuth \par} 
\stoptext
