diff --git a/LICENSE b/LICENSE
index d5075a3..6b5e79c 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,3 +1,5 @@
+Copyright (C) Zed A. Shaw. All Rights Reserved.
+
 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the
diff --git a/Makefile b/Makefile
index fa86918..ca71ab6 100644
--- a/Makefile
+++ b/Makefile
@@ -30,20 +30,20 @@ test: build
 
 run: build test
 ifeq '$(OS)' 'Windows_NT'
-	powershell "cp ./builddir/calculator.exe ."
-	./calculator
+	powershell "cp ./builddir/calc.exe ."
+	./calc
 else
-	./builddir/calculator
+	./builddir/calc
 endif
 
 debug: build
-	gdb --nx -x .gdbinit --ex run --args builddir/calculator
+	gdb --nx -x .gdbinit --ex run --args builddir/calc
 
 debug_run: build
-	gdb --nx -x .gdbinit --batch --ex run --ex bt --ex q --args builddir/calculator
+	gdb --nx -x .gdbinit --batch --ex run --ex bt --ex q --args builddir/calc
 
 debug_walk: build test
-	gdb --nx -x .gdbinit --batch --ex run --ex bt --ex q --args builddir/calculator t
+	gdb --nx -x .gdbinit --batch --ex run --ex bt --ex q --args builddir/calc t
 
 clean:
 	meson compile --clean -C builddir
diff --git a/guecs.cpp b/guecs.cpp
index 22dba4b..dc53757 100644
--- a/guecs.cpp
+++ b/guecs.cpp
@@ -1,7 +1,7 @@
 #include "guecs.hpp"
-#include "shaders.hpp"
-#include "sound.hpp"
-#include "textures.hpp"
+#include "sfml/shaders.hpp"
+#include "sfml/sound.hpp"
+#include "sfml/textures.hpp"
 #include <typeinfo>
 
 namespace guecs {
diff --git a/guecs.hpp b/guecs.hpp
index 38966d8..e1b708f 100644
--- a/guecs.hpp
+++ b/guecs.hpp
@@ -1,6 +1,6 @@
 #pragma once
 #include "dbc.hpp"
-#include "color.hpp"
+#include "sfml/color.hpp"
 #include "lel.hpp"
 #include <string>
 #include <memory>
diff --git a/guecstra.cpp b/guecstra.cpp
deleted file mode 100644
index 915b8a1..0000000
--- a/guecstra.cpp
+++ /dev/null
@@ -1,18 +0,0 @@
-#include "guecstra.hpp"
-
-namespace guecs {
-
-  Clickable make_action(DinkyECS::World& target, Events::GUI event) {
-    return {[&, event](auto ent, auto data){
-      // remember that ent is passed in from the UI::mouse handler
-      target.send<Events::GUI>(event, ent, data);
-    }};
-  }
-
-  Clickable make_action(DinkyECS::World& target, Events::GUI event, std::any data) {
-    return {[&, event, data](auto ent, auto){
-      // remember that ent is passed in from the UI::mouse handler
-      target.send<Events::GUI>(event, ent, data);
-    }};
-  }
-}
diff --git a/guecstra.hpp b/guecstra.hpp
deleted file mode 100644
index b9d62b3..0000000
--- a/guecstra.hpp
+++ /dev/null
@@ -1,7 +0,0 @@
-#include "components.hpp"
-#include "guecs.hpp"
-
-namespace guecs {
-  Clickable make_action(DinkyECS::World& target, Events::GUI event);
-  Clickable make_action(DinkyECS::World& target, Events::GUI event, std::any data);
-}
diff --git a/meson.build b/meson.build
index 902d2a4..dcedec4 100644
--- a/meson.build
+++ b/meson.build
@@ -82,9 +82,9 @@ sources = [
   'dbc.cpp',
   'guecs.cpp',
   'lel.cpp',
-  'shaders.cpp',
-  'sound.cpp',
-  'textures.cpp',
+  'sfml/shaders.cpp',
+  'sfml/sound.cpp',
+  'sfml/textures.cpp',
 ]
 
 executable('runtests', sources + [
@@ -98,3 +98,11 @@ executable('runtests', sources + [
   link_args: link_args,
   override_options: exe_defaults,
   dependencies: dependencies + [catch2])
+
+executable('calc', sources + [
+  'demos/calc.cpp',
+  ],
+  cpp_args: cpp_args,
+  link_args: link_args,
+  override_options: exe_defaults,
+  dependencies: dependencies)
diff --git a/color.hpp b/sfml/color.hpp
similarity index 100%
rename from color.hpp
rename to sfml/color.hpp
diff --git a/shaders.cpp b/sfml/shaders.cpp
similarity index 100%
rename from shaders.cpp
rename to sfml/shaders.cpp
diff --git a/shaders.hpp b/sfml/shaders.hpp
similarity index 100%
rename from shaders.hpp
rename to sfml/shaders.hpp
diff --git a/sound.cpp b/sfml/sound.cpp
similarity index 100%
rename from sound.cpp
rename to sfml/sound.cpp
diff --git a/sound.hpp b/sfml/sound.hpp
similarity index 100%
rename from sound.hpp
rename to sfml/sound.hpp
diff --git a/textures.cpp b/sfml/textures.cpp
similarity index 100%
rename from textures.cpp
rename to sfml/textures.cpp
diff --git a/textures.hpp b/sfml/textures.hpp
similarity index 100%
rename from textures.hpp
rename to sfml/textures.hpp
diff --git a/tests/guecs.cpp b/tests/guecs.cpp
index 3b41065..016971a 100644
--- a/tests/guecs.cpp
+++ b/tests/guecs.cpp
@@ -2,7 +2,7 @@
 #include <fmt/core.h>
 #include "constants.hpp"
 #include "guecs.hpp"
-#include "textures.hpp"
+#include "sfml/textures.hpp"
 #include <fmt/xchar.h>
 
 using namespace guecs;
diff --git a/tests/shaders.cpp b/tests/shaders.cpp
index 2b210ff..79b9e71 100644
--- a/tests/shaders.cpp
+++ b/tests/shaders.cpp
@@ -1,7 +1,7 @@
 #include <catch2/catch_test_macros.hpp>
 #include <fmt/core.h>
 #include <string>
-#include "shaders.hpp"
+#include "sfml/shaders.hpp"
 
 using namespace fmt;
 
diff --git a/tests/sound.cpp b/tests/sound.cpp
index 968e650..09d7329 100644
--- a/tests/sound.cpp
+++ b/tests/sound.cpp
@@ -1,7 +1,7 @@
 #include <catch2/catch_test_macros.hpp>
 #include <fmt/core.h>
 #include <string>
-#include "sound.hpp"
+#include "sfml/sound.hpp"
 
 using namespace fmt;
 
diff --git a/tests/textures.cpp b/tests/textures.cpp
index 910bda8..4ead2c0 100644
--- a/tests/textures.cpp
+++ b/tests/textures.cpp
@@ -1,7 +1,7 @@
 #include <catch2/catch_test_macros.hpp>
 #include <fmt/core.h>
 #include <string>
-#include "textures.hpp"
+#include "sfml/textures.hpp"
 
 using namespace fmt;