\enabletrackers[metapost.graphics]

\starttext

\startMPpage
    fill fullcircle scaled 4cm withcolor blue ;
    label.top(btex \color[white]{\bf This is a test.} etex, origin);
\stopMPpage

\setuplayout[width=middle,height=middle,topspace=1cm,backspace=1cm,header=1cm]

\setupbodyfont[9pt]

\typefile[lines=yes]{tracing-001.tex}

\page

\typefile[lines=yes]{tracing-001-mplib-run-001.mp}

\stoptext
