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( Subset of Forth94 )

The bootstrapping process uses a metacompiler written in Lisp to
target a small inner interpreter and a handful of code words written
in C.  There is also a new metacompiler written in Forth which is
intended to replace the Lisp version in the future.  Work is under way
to add a real target using assembly language code words.

( Further reading )

INSTALL          \ How to build.
doc              \ Classic (and recent) texts not related to this project.
lib/README       \ Information about libraries.
targets/README   \ Information about current and possibly future targets.

( Implementation guide )

The Forth kernel contains everything needed to read and compile the
rest of the system from source code, and not much else.  It's composed
of two parts: a target-specific file nucleus.fth containing all
primitive CODE words, and a target-independent kernel.fth.  These two
are compiled by the metacompiler.

The C target nucleus used for bootstrapping has only twelve proper
primitives.  There is also the COLD word which compiles to main(), a
signal handler, and four I/O words.

When the kernel starts, it jumps to the word called WARM.  This is
responsible for loading the rest of the system and entering the text
interpreter.  The first file loaded by WARM is core.fth, which
implements the CORE wordset.  Because the kernel only has a bare
minimum of words, the start of core.fth looks a little strange.