Needed to add the default_library=static option for Windows, but I believe that fails on OSX.

sfmldemo/meson.build

@@ -1,5 +1,6 @@
 project('sfmldemo', 'cpp',
   default_options: [
+    'default_library=static',
     'cpp_std=c++17',
     ])
 
@@ -9,4 +10,5 @@ fmt_dep = dependency('fmt')
 
 executable('sfmldemo', 'main.cpp',
   win_subsystem: 'windows',
+  cpp_args: '-DFMT_HEADER_ONLY',
   dependencies: [sfml_dep, imgui_dep, fmt_dep])

sfmldemo/reset_build.ps1

@@ -0,0 +1,17 @@
+mv .\subprojects\packagecache .
+rm -recurse -force .\subprojects\,.\builddir\
+mkdir subprojects
+mv .\packagecache .\subprojects\
+mkdir builddir
+meson wrap install flac
+meson wrap install freetype2
+meson wrap install imgui-sfml
+meson wrap install imgui
+meson wrap install libpng
+meson wrap install ogg
+meson wrap install openal-soft
+meson wrap install sfml
+meson wrap install vorbis
+meson wrap install zlib
+meson wrap install fmt
+meson setup builddir