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Since April 2019, there is a new implementation of ConTeXt, named '''ConTeXt [[LMTX]]'''. It is tuned for LuaMetaTeX, the lean and mean successor of the LuaTeX engine. From Hans' introductory article in TUGBoat:: More than decade after introducing the ConTeXt version for LuaTeX, flagged [[MkIV]] (the version known as [[MkII]] ran under more traditional TeX engines), it is time for something new. As MkVI, MkIX and MkXI are already taken for special variants of MkIV files a new acronym was coined: LMTX. Such a sequence of letters must sound somewhat fancy but it actually has a meaning, or better: it has several. One is that it stands for LuaMetaTeX, an indication of an engine to be used. But one can also think of the components that make up ConTeXt code: Lua, MetaPost, TeX , and XML. But once it is clear to a user what (s)he is dealing with, it can also indicate a “Lean and Mean TeX eXperience”. == The LuaMetaTeX engine == The big difference between LMTX and all previous versions of ConTeXt is that LMTX uses a compilation and scripting engine that is specifically developed with ConTeXt in mind: LuaMetaTeX (the executable is named `luametatex`). This new engine builds heavily on the LuaTeX engine , but it has been optimised heavily for ConTeXt use: * There are no external dependencies except for thee core `libc` and `libm` runtimes* There is no PDF backend code, all PDF generation is handled by ConTeXt's Lua code* There is no `fontloader` lua interface library, (OpenType) font loading is handled by ConTeXt's Lua code* There are no `img` and `pdf` (poppler-based) lua interface libraries (the latter is replaced by the leaner dedicated library `epdf`)* Various extensions have been made to other lua interface libraries When it comes to typesetting, `luametatex` is (at least for now) 100% compatible with LuaTeX > 1.0. == The LMTX distribution == Some extra scripting extensions in the engine have made it much easier to produce a standalone distribution of ConTeXt that is not only compact, but also capable of partial updates. See [[Installation]] for the new installation and update process. Of course the new distribution defaults to running LMTX. But it can still process input using LuaTeX (see [[MkIV]]) as well. You can do this by running <pre> context --luatex</pre>This works because the distribution contains all of the [[MkIV]] source code as well as a `luatex` binary. The new installation no longer contains the [[MkII]] source code or binaries, and is therefore unable to run it.   = Further reading =* Hans' introductory [https://tug.org/TUGboat/tb40-1/tb124hagen-lmtx.pdf article])in TUGBoat 40:1.* The official page '''[http://www.pragma-ade.com/install.htm Installing CONTEXT LMTX ]''' is hosted by Pragma-Ade, which also provides** a 2 pages '''[http://lmtx.pragma-ade.nl/install-lmtx/installation.pdf installation guide]''',** a 1 page [http://distribution.contextgarden.net/current/context/experimental/doc/context/documents/general/leaflets/leaflet-context.pdf leaflet for ConTeXt LMTX]** a 1 page [http://distribution.contextgarden.net/current/context/experimental/doc/context/documents/general/leaflets/leaflet-luametatex.pdf leaflet for LuaMetaTeX].