On 2013–04–20 Hans Hagen wrote:

> >1) Create a file “luatex-plain.tex” with the following context:
> >
> >\input plain
> >\directlua {tex.enableprimitives('', tex.extraprimitives())}
> >\pdfoutput=1
> >\everyjob \expandafter {%
> >     \the\everyjob
> >     \input luatex-basics\relax
> >     \input luatex-fonts\relax
> >     \input luatex-mplib\relax
> >}
> >\edef\fmtversion{\fmtversion+luatex}
> >\dump
> 
> there is a luatex-plain.tex in the context distribution

Indeed. That's probably where I got the snippet from.

@Tim: That means running

  luatex --ini luatex-plain.tex

is sufficient.


Marco