I've just found an article PerlTeX: Defining LaTeX macros using Perl by Scott Pakin, published in TUGboat 25(2) 2004.
In the section "Related work", the author writes about sTeXme:
sTeXme, which uses Scheme rather than Perl as the TeX extension language. sTeXme adds a single command to TeX: \stexme, which works like \input but accepts the name of a Scheme file rather than a TeX or LaTeX file. When the Scheme interpreter evaluates the given file, output procedures such as newline and display write into the TeX input stream. Two new procedures, pool-string and get-cmd, provide access to TeX internal state. As with Shibakov's PerlTeX, sTeXme's tight integration with TeX comes at the cost of having to recompile TeX and re-dump all of the format files before the extension language can be used.... read more
The concept release of sTeXme revealed the following.
* Using Scheme as a TeX extension language is a perspective method.
* My approach to implementation is failed.
Or maybe not failed, but I see the better way. There is no need to write a C layer between generated C and Guile. Instead, we can convert TeX source code to Scheme and seamlessly use Scheme for writing extensions.
Unfortunately, I have no time to work on the project, so I'd like to find someone also who can. I can provide some funding. See RAC: http://rentacoder.com/RentACoder/misc/BidRequests/ShowBidRequest.asp?lngBidRequestId=292832
It seems sTeXme was mentioned at EuroTeX 2005. I've just stumbled upon the preprint of Jonathan Fine's talk "TeX Forever!". He mentions sTeXme several times, and I'm very pleased with his writing. I couldn't write better! Thanks you, Jonathan.
EuroTeX 2005: http://www.gutenberg.eu.org/eurotex2005/en/157-intro.html
The preprint: http://www.dante.de/dante/events/eurotex/papers/MOT10.pdf
The [La]TeX macro language was a great development when it appeared, but now it is too out-of-date. Programming in TeX is a fun, but more often it is a pain.
As it seems for me, only very few people can write [La]TeX macros, but a lot of people would like doing it (like me, for example). This is the problem.
One of the solutions is to provide another scripting language for TeX. That's what is the goal of the sTeXme project. It should provide the Scheme programming language as a TeX scripting language.... read more
The "sTeXme" TeX extension allows to manipulate TeX internals from the Scheme programming language.
Proof of the concept code is just released. It is based on teTeX and Guile. Unfortunately, there are issues which I can't fix right now and in the near future.
* build process: it is naive and error-prone now. It is better to integrate building of sTeXme into the process of building of tetex.
* use of kpathsee: see http://sourceforge.net/tracker/index.php?func=detail&aid=1082988&group_id=125882&atid=704010
* reuse of the constants: see http://sourceforge.net/tracker/index.php?func=detail&aid=1082993&group_id=125882&atid=704010