#+COMMENT:                                                            -*- org -*-
#+TITLE: About GNU Mes

#+SUBTITLE: Maxwell Equations of Software

[[https://www.gnu.org/software/mes][GNU Mes]] is a Scheme interpreter and C compiler for bootstrapping the GNU
System.  Since version 0.22 it has again helped to halve the size of
opaque, uninspectable binary seeds that are currently being used in the
[[https://guix.gnu.org/blog/2019/guix-reduces-bootstrap-seed-by-50/][Reduced Binary Seed bootstrap]] of [[https://www.gnu.org/software/guix][GNU Guix]].  The final goal is to help
create a full source bootstrap as part of the [[http://bootstrappable.org][bootstrappable builds]]
effort for UNIX-like operating systems.

The Scheme interpreter is written in ~5,000 LOC of simple C, and the C
compiler written in Scheme and these are mutual self-hosting.  Mes can
now be bootstrapped by [[https://github.com/oriansj/m2-planet][M2-Planet]] and [[https://savannah.nongnu.org/projects/mescc-tools][Mescc-Tools]].

Mes has a Garbage Collector, a library of loadable Scheme modules--
notably Dominique Boucher's [[https://github.com/schemeway/lalr-scm][LALR]], Pre-R6RS [[https://www.cs.indiana.edu/chezscheme/syntax-case/old-psyntax.html][portable syntax-case]] with
R7RS ellipsis, Matt Wette's [[https://www.nongnu.org/nyacc][Nyacc]] --and test suite, just enough to
support a REPL and a C99 compiler: mescc.

Mes + MesCC + Mes C Library can build a [[https://gitlab.com/janneke/tinycc][bootstrappable TinyCC]] that is
self-hosting.  Using this tcc and the Mes C library we now have a
Reduced Binary Seed bootstrap for the gnutools triplet: glibc-2.2.5,
binutils-2.20.1, gcc-2.95.3.  This is enough to bootstrap Guix for
i686-linux, x86_64-linux, armhf-linux and aarch64-linux.

Mes is inspired by The Maxwell Equations of Software: [[http://www.softwarepreservation.org/projects/LISP/book/LISP%201.5%20Programmers%20Manual.pdf][LISP-1.5]] -- John
McCarthy page 13, GNU Guix's source/binary packaging transparency and
Jeremiah Orians's [[https://github.com/oriansj/stage0][stage0]] ~500 byte self-hosting hex assembler.

We are very grateful to NLNet for sponsoring the
[[https://nlnet.nl/project/GNUMes][Reduced Binary Seed bootstrap]] and the [[https://nlnet.nl/project/GNUMes-arm][ARM port]].

GNU Mes is free software, it is distributed under the terms of the GNU
General Public Licence version 3 or later.  See the file [[file:COPYING][COPYING]].

* Get it

   #+BEGIN_SRC bash
   git clone git://git.savannah.gnu.org/mes.git
   #+END_SRC

* Build it (see [[file:INSTALL][INSTALL]] for full instructions)

   #+BEGIN_SRC bash
   ./configure
   make all
   make check
   #+END_SRC

* REPL it

   #+BEGIN_SRC bash
   ./pre-inst-env mes
   #+END_SRC

* MesCC compiler

   #+BEGIN_SRC bash
   ./pre-inst-env mescc -c scaffold/main.c
   #+END_SRC

* Bugs

    Please send Mes bug reports to [[mailto:bug-mes@gnu.org][bug-mes@gnu.org]].

* Links
  [0] https://www.gnu.org/software/mes
  [1] https://guix.gnu.org/blog/2020/guix-further-reduces-bootstrap-seed-to-25
  [2] https://www.gnu.org/software/guix
  [3] https://bootstrappable.org
  [4] https://github.com/oriansj/m2-planet
  [5] https://savannah.nongnu.org/projects/mescc-tools
  [6] https://github.com/schemeway/lalr-scm
  [7] https://www.cs.indiana.edu/chezscheme/syntax-case/old-psyntax.html
  [8] https://www.nongnu.org/nyacc
  [9] https://gitlab.com/janneke/tinycc
  [10] [[http://www.softwarepreservation.org/projects/LISP/book/LISP%201.5%20Programmers%20Manual.pdf]]
  [11] https://savannah.nongnu.org/projects/stage0
  [12] https://nlnet.nl/project/GNUMes
  [13] https://nlnet.nl/project/GNUMes-arm

* Legalese
Copyright © 2016,2017,2018,2019,2020,2021 Jan (janneke) Nieuwenhuizen <[[mailto:janneke@gnu.org][janneke@gnu.org]]>

  Copying and distribution of this file, with or without modification,
  are permitted in any medium without royalty provided the copyright
  notice and this notice are preserved.
