diff --git a/samples/fluid/build.bat b/samples/fluid/build.bat
index c01c970..5395ce1 100644
--- a/samples/fluid/build.bat
+++ b/samples/fluid/build.bat
@@ -27,7 +27,9 @@ set shaders=src/shaders/advect.glsl^
 	src/shaders/subtract_pressure.glsl
 
 call python3 ../../milepost/scripts/embed_text.py --prefix=glsl_ --output src/glsl_shaders.h %shaders%
+IF %ERRORLEVEL% NEQ 0 EXIT /B %ERRORLEVEL%
 
 clang %wasmFlags% -o .\module.wasm ..\..\sdk\orca.c ..\..\cstdlib\src\*.c src\main.c
+IF %ERRORLEVEL% NEQ 0 EXIT /B %ERRORLEVEL%
 
-python3 ..\..\scripts\mkapp.py --orca-dir ..\.. --icon icon.png --name Fluid module.wasm
+orca bundle --orca-dir ..\.. --icon icon.png --name Fluid module.wasm
diff --git a/samples/glesTriangle/build.bat b/samples/glesTriangle/build.bat
index add38e3..60d97e4 100644
--- a/samples/glesTriangle/build.bat
+++ b/samples/glesTriangle/build.bat
@@ -13,5 +13,6 @@ set wasmFlags=--target=wasm32^
        -isystem ..\..\cstdlib\include -I ..\..\sdk -I..\..\milepost\ext -I ..\..\milepost -I ..\..\milepost\src
 
 clang %wasmFlags% -o .\module.wasm ..\..\sdk\orca.c ..\..\cstdlib\src\*.c src\main.c
+IF %ERRORLEVEL% NEQ 0 EXIT /B %ERRORLEVEL%
 
-python3 ..\..\scripts\mkapp.py --orca-dir ..\.. --name Triangle module.wasm
+orca bundle --orca-dir ..\.. --name Triangle module.wasm
diff --git a/samples/pong/build.bat b/samples/pong/build.bat
index 4cd29cb..66c17f1 100644
--- a/samples/pong/build.bat
+++ b/samples/pong/build.bat
@@ -13,5 +13,6 @@ set wasmFlags=--target=wasm32^
        -isystem ..\..\cstdlib\include -I ..\..\sdk -I..\..\milepost\ext -I ..\..\milepost -I ..\..\milepost\src
 
 clang %wasmFlags% -o .\module.wasm ..\..\sdk\orca.c ..\..\cstdlib\src\*.c src\main.c
+IF %ERRORLEVEL% NEQ 0 EXIT /B %ERRORLEVEL%
 
 orca bundle --orca-dir ..\.. --name Pong --icon icon.png --resource-dir data module.wasm
diff --git a/samples/ui/build.bat b/samples/ui/build.bat
index 5717a40..9befcf7 100644
--- a/samples/ui/build.bat
+++ b/samples/ui/build.bat
@@ -13,5 +13,6 @@ set wasmFlags=--target=wasm32^
        -isystem ..\..\cstdlib\include -I ..\..\sdk -I..\..\milepost\ext -I ..\..\milepost -I ..\..\milepost\src
 
 clang %wasmFlags% -o .\module.wasm ..\..\sdk\orca.c ..\..\cstdlib\src\*.c src\main.c
+IF %ERRORLEVEL% NEQ 0 EXIT /B %ERRORLEVEL%
 
 orca bundle --orca-dir ..\.. --name UI --resource-dir data module.wasm