diff --git a/README.md b/README.md
index 4c8241e..b075178 100644
--- a/README.md
+++ b/README.md
@@ -72,12 +72,18 @@ target_link_libraries(your_target PRIVATE ikv::ikv)
 
 ### Script build
 
-For the repo-local non-CMake build path used in CI:
+For the repo-local non-CMake build path:
 
 ```sh
 ./demo/build.sh
 ```
 
+On Windows:
+
+```bat
+demo\build.bat
+```
+
 ## Project layout
 
 - `include/ikv.h`: public API
@@ -122,4 +128,3 @@ To add a new format version:
 2. Implement the loader
 3. Register it in `src/ikv.c`
 4. Add a public version constant to `include/ikv.h` if needed
-
diff --git a/demo/build.bat b/demo/build.bat
new file mode 100644
index 0000000..04875d1
--- /dev/null
+++ b/demo/build.bat
@@ -0,0 +1,77 @@
+@echo off
+setlocal EnableExtensions
+
+set "SCRIPT_DIR=%~dp0"
+for %%I in ("%SCRIPT_DIR%..") do set "ROOT_DIR=%%~fI"
+set "OUT_DIR=%SCRIPT_DIR%build"
+set "DEMO_EXE=%OUT_DIR%\ikv_demo.exe"
+set "TEST_EXE=%OUT_DIR%\ikv_tests.exe"
+
+if not exist "%OUT_DIR%" mkdir "%OUT_DIR%"
+
+set "CC="
+where gcc >nul 2>nul && set "CC=gcc"
+if not defined CC where clang >nul 2>nul && set "CC=clang"
+
+if defined CC goto :build_with_cc
+
+where cl >nul 2>nul
+if errorlevel 1 goto :no_compiler
+goto :build_with_cl
+
+:build_with_cc
+"%CC%" -std=c11 -Wall -Wextra -pedantic ^
+    -I"%ROOT_DIR%\include" ^
+    "%SCRIPT_DIR%main.c" ^
+    "%ROOT_DIR%\src\ikv.c" ^
+    "%ROOT_DIR%\src\loaders\ikv1.c" ^
+    "%ROOT_DIR%\src\loaders\ikv2.c" ^
+    -o "%DEMO_EXE%"
+if errorlevel 1 exit /b 1
+
+"%CC%" -std=c11 -Wall -Wextra -pedantic ^
+    -DIKV_TESTING ^
+    -I"%ROOT_DIR%\include" ^
+    "%SCRIPT_DIR%unit_test.c" ^
+    "%ROOT_DIR%\src\ikv.c" ^
+    "%ROOT_DIR%\src\loaders\ikv1.c" ^
+    "%ROOT_DIR%\src\loaders\ikv2.c" ^
+    -o "%TEST_EXE%"
+if errorlevel 1 exit /b 1
+goto :after_build
+
+:build_with_cl
+cl /nologo /std:c11 /W4 /I "%ROOT_DIR%\include" ^
+    "%SCRIPT_DIR%main.c" ^
+    "%ROOT_DIR%\src\ikv.c" ^
+    "%ROOT_DIR%\src\loaders\ikv1.c" ^
+    "%ROOT_DIR%\src\loaders\ikv2.c" ^
+    /Fe:"%DEMO_EXE%"
+if errorlevel 1 exit /b 1
+del /q "%SCRIPT_DIR%*.obj" 2>nul
+
+cl /nologo /std:c11 /W4 /DIKV_TESTING /I "%ROOT_DIR%\include" ^
+    "%SCRIPT_DIR%unit_test.c" ^
+    "%ROOT_DIR%\src\ikv.c" ^
+    "%ROOT_DIR%\src\loaders\ikv1.c" ^
+    "%ROOT_DIR%\src\loaders\ikv2.c" ^
+    /Fe:"%TEST_EXE%"
+if errorlevel 1 exit /b 1
+del /q "%SCRIPT_DIR%*.obj" 2>nul
+del /q "%SCRIPT_DIR%*.ilk" 2>nul
+del /q "%SCRIPT_DIR%*.pdb" 2>nul
+
+:after_build
+echo built "%DEMO_EXE%"
+echo built "%TEST_EXE%"
+
+if /I "%~1"=="test" (
+    "%TEST_EXE%"
+    exit /b %errorlevel%
+)
+
+exit /b 0
+
+:no_compiler
+echo No supported C compiler found. Install gcc, clang, or run from a Visual Studio developer prompt.>&2
+exit /b 1