Hello,

I'm the developer of the kerTeX TeX and al. distribution.

kerTeX has, of course TeX and e-TeX, but not other engines.

The first "engine" modification of LaTeX, a few months ago, was to
request the e-TeX extensions and drop vanilla TeX. OK, done.

Now the last modification requires extensions not present in e-TeX.

Until now I was able to provide the kerTeX users with a LaTeX package
(I'm not myself a LaTeX user). I will not be able to follow if this
stays the same way.

So I'd like to have a clear understanding of the issues:

1) Is LaTeX3 aimed to be a "TeX" free engine, that is will not run on a
TeX (at least a e-TeX) engine in the future?

2) If this step is taken, can you provide on CTAN a latex2e link to the
last TeX compatible version (for the moment, latex2e points to the
latest latex that is, IIUC, latex3...)?

3) What are the so crucial primitives, not present in TeX or e-TeX,
that it is not possible to treat them as possible extensions, been
tested against for conditional treatment inclusions, but have to be
absolute required ones? If they do exist, and have nothing
to do with post-processing that is printing specially in PDF (which 
should be deferred to post-processing utilities), are there change files
to be applied to e-TeX in order to create a special engine meeting your
requirements?

4) Are the modifications so deep that for the hundreds of LaTeX related
macros already written, they will have to be rewritten to continue to be
compatible with LaTeX3?

Thanks in advance for clarifications!
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                     http://www.kergis.com/
                http://www.kergis.com/kertex.html
                       http://www.sbfa.fr/
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