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 <para>

   The &SCons; tool provides an easy-to-use, feature-rich interface
   for constructing software.  Architecturally, &SCons; separates
   its dependency analysis and external object management into an
   interface-independent Build Engine that could be embedded in any
   software system that can run Python.

 </para>

 <para>

   At the command line, &SCons; presents an easily-grasped tool
   where configuration files are Python scripts, reducing the need
   to learn new build-tool syntax. Inexperienced users can use
   intelligent methods that ``do the right thing'' to build software
   with a minimum of fuss. Sophisticated users can use a rich set
   of underlying features for finer control of the build process,
   including mechanisms for easily extending the build process to new
   file types.
   
 </para>
 
 <para>
 
   Dependencies are tracked using digital signatures,
   which provide more robust dependency analysis than file time
   stamps. Implicit dependencies are determined automatically by
   scanning the contents of source files, avoiding the need for
   laborious and fragile maintenance of static lists of dependencies in
   configuration files.
   
 </para>

 <para>

   The &SCons; tool supports use of files from one or more central code
   repositories, a mechanism for caching derived files, and parallel
   builds.  The tool also includes a framework for sharing build
   environments, which allows system administrators or integrators to
   define appropriate build parameters for use by other users.

 </para>

<section id="sect-document">
 <title>About This Document</title>

 <para>

   This document is an ongoing work-in-progress to write down the ideas
   and tradeoffs that have gone, and will go into, the &SCons; design.
   As such, this is intended primarily for use by developers and others
   working on &SCons;, although it is also intended to serve as a
   detailed overview of &SCons; for other interested parties.  It will
   be continually updated and evolve, and will likely overlap with other
   documentation produced by the project.  Sections of this document
   that deal with syntax, for example, may move or be copied into a user
   guide or reference manual.

 </para>

 <para>

   So please don't assume that everything mentioned here has been
   decided and carved in stone.  If you have ideas for improvements, or
   questions about things that don't seem to make any sense, please help
   improve the design by speaking up about them.

 </para>

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comments about the document
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but also to cite some open design issues.
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</section>