diff --git a/Makefile b/Makefile
index 854b259..0b0d566 100644
--- a/Makefile
+++ b/Makefile
@@ -11,16 +11,17 @@ ordos.img: BOOT.BIN IO.SYS ORDOS.SYS COMMAND.COM debug.com edlin.com exe2bin.exe
 	mcopy -i $@ link.exe ::
 	mcopy -i $@ masm.exe ::
 
-BOOT.BIN IO.SYS ORDOS.SYS COMMAND.COM:
-	dosbox -exit build.bat
-
 BOOT.BIN: boot.asm
+	dosbox -exit mk-boot.bat
 
 IO.SYS: io.asm
+	dosbox -exit mk-io.bat
 
 ORDOS.SYS: msdos.asm stddos.asm
+	dosbox -exit mk-ordos.bat
 
 COMMAND.COM: command.asm
+	dosbox -exit mk-comma.bat
 
 clean:
 	rm -f ordos.img
diff --git a/build.bat b/build.bat
deleted file mode 100644
index b12c88e..0000000
--- a/build.bat
+++ /dev/null
@@ -1,15 +0,0 @@
-masm command;
-link command;
-exe2bin command.exe command.com
-
-masm stddos;
-link stddos;
-exe2bin stddos.exe ordos.sys
-
-masm boot;
-link boot;
-exe2bin boot.exe boot.bin
-
-masm io;
-link io;
-exe2bin io.exe io.sys
diff --git a/mk-boot.bat b/mk-boot.bat
new file mode 100644
index 0000000..af0405e
--- /dev/null
+++ b/mk-boot.bat
@@ -0,0 +1,3 @@
+masm boot;
+link boot;
+exe2bin boot.exe boot.bin
diff --git a/mk-comma.bat b/mk-comma.bat
new file mode 100644
index 0000000..15ed756
--- /dev/null
+++ b/mk-comma.bat
@@ -0,0 +1,3 @@
+masm command;
+link command;
+exe2bin command.exe command.com
diff --git a/mk-io.bat b/mk-io.bat
new file mode 100644
index 0000000..361cc14
--- /dev/null
+++ b/mk-io.bat
@@ -0,0 +1,3 @@
+masm io;
+link io;
+exe2bin io.exe io.sys
diff --git a/mk-ordos.bat b/mk-ordos.bat
new file mode 100644
index 0000000..f9398b4
--- /dev/null
+++ b/mk-ordos.bat
@@ -0,0 +1,3 @@
+masm stddos;
+link stddos;
+exe2bin stddos.exe ordos.sys