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+****************************************************************************************
+**  DO NOT RUN THE APPIMAGE BUILD ON A PRODUCTION MACHINE!  IT WILL ERASE YOUR DATA!  **
+****************************************************************************************
+
+The tooling in this directory can be used to build an AppImage, the entire Citadel System
+distributed as a single binary file.  Visit https://appimage.org/ to learn more about the
+AppImage format and how it works.
+
+Again, do NOT try to run this on your production machine.  For that matter, don't try to
+run it on anything other than a dedicated build host.  It will ERASE /usr/local/citadel
+and /usr/local/webcit during the build process.
+
+If you're an end user you shouldn't have any need to do this at all.  The whole point of
+this is that we can supply ready-to-run binaries that will run on any Linux/Linux system
+without modification or dependencies.  If you are an end user, stop here, go download the
+binary package, and use it.  Enjoy it and have fun.
+
+Still with us?  Then you must be a new member of the Citadel team and you're packaging
+the software for a new architecture or something.  So here's what you have to do to build
+the binary:
+
+1. Download the Citadel source tree (if you're reading this, you've already done that).
+2. Install all system dependencies.  The same ones needed for Easy Install are fine.
+3. Download and install "appimagetool" from appimage.org.
+4. Run "./build_appimage.sh"
+
+What's going to happen next?
+
+1. Any existing /usr/local/citadel and /usr/local/webcit will be erased.
+2. The script will go through the source tree, building and installing libcitadel,
+   the Citadel server, and WebCit into the /usr/local hierarchy.
+3. All binaries, static data, and libraries will be copied into the citadel.AppDir
+   tree.
+4. appimagetool will be called, and it will generate an executable with a
+   name like "Citadel-x64.AppImage".   This is your distributable binary.  Upload
+   it somewhere fun.
+
+You should be running this build on the OLDEST version of Linux/Linux on which your
+binary should be able to run.  The distribution does not matter -- for example, a
+binary built on Debian should run fine on Ubuntu or Red Hat or whatever -- but the C
+library and other very base system libraries are only upward compatible, not downward
+compatible.  For example, at the time of this writing, I am building on Ubuntu 14 and
+it's early 2021.