Hey, nice. Lots to learn still, but this is working.

config.nims

@@ -1,5 +1,5 @@
 
-when defined(emscripten):
+when defined( emscripten ):
   --define:GraphicsApiOpenGlEs2
   # --define:NaylibWebResources
   # switch("define", "NaylibWebResourcesPath=resources")
@@ -8,20 +8,27 @@ when defined(emscripten):
   --os:linux
   --cpu:wasm32
   --cc:clang
-  --clang.exe:emcc
-  --clang.linkerexe:emcc
-  --clang.cpp.exe:emcc
-  --clang.cpp.linkerexe:emcc
+  when defined( windows ):
+    --clang.exe:emcc.bat  # Replace C
+    --clang.linkerexe:emcc.bat # Replace C linker
+    --clang.cpp.exe:emcc.bat # Replace C++
+    --clang.cpp.linkerexe:emcc.bat # Replace C++ linker.
+  else:
+    --clang.exe:emcc
+    --clang.linkerexe:emcc
+    --clang.cpp.exe:emcc
+    --clang.cpp.linkerexe:emcc
   --mm:arc
   --threads:on
   --panics:on
   --exceptions:goto
   --define:noSignalHandler
-  --passL:"-03"
+  --passL:"-Oz" # Production build
+  # --passL:"-O0 -gDebug -gsource-map" # Debug build
   # --passL:"-s EXPORT_NAME=Test1Module"
   # --passL:"-s MODULARIZE=1"
   --passL:"-s ASYNCIFY" # async support
   # --passL:"-s JSPI" # async support
-  --passL:"-o index.html"
-  # --passL:"--shell-file minshell.html"
+  --passL:"-o build/index.html"
+  --passL:"--shell-file minshell.html"