{E-\TeX: Guidelines for future \TeX{} extensions, revisited}
{Frank Mittelbach}
{Shortly after Don Knuth announced \TeX~3.0 I gave a paper analyzing
\TeX{}'s abilities as a typesetting engine.
The abstract back then said:
%\begin{quote}
{\par \leftskip=8pt % \parindent is 16pt
Now it is time, after ten years'
experience, to step back and consider whether or not \TeX{}~3.0
is an adequate answer to the typesetting requirements of the
nineties.

Output produced by \TeX{} has higher standards than
  output
generated automatically by
  most other typesetting systems.
Therefore, in
  this paper we
will
focus on the quality standards set by
typographers for
hand-typeset
  documents and ask
to what extent they are achieved by \TeX.  Limitations of
\TeX{}'s algorithms are analyzed;
and
  missing features as well
as new concepts are
outlined.
\par}%\end{quote}

Now\Dash two decades later\Dash it is time to take another look and see what
has been achieved since then, and perhaps more importantly, what can be
achieved now with computer power having multiplied by a huge factor and
last not least by the arrival of a number of successors to \TeX{} which
have lifted some of the limitations identified back then.

}