Achim Blumensath's ANT project, in contrast to NTS, aims not to replicate TeX with a different implementation technique, but rather to provide a replacement for TeX which uses TeX-like typesetting algorithms in a very different programming environment. ANT remains under development, but it is now approaching the status of a usable typesetting system.
ANT's markup language is immediately recognisable to the (La)TeX user, but the scheme of implementing design in ANT's own implementation language (presently OCaml) comes as a pleasant surprise to the jaded FAQ writer. This architecture holds the promise of a system that avoids a set of serious problems with TeX's user interface: those that derive from the design language being the same as the markup language.
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