diff --git a/Makefile-dsk.mk b/Makefile-dsk.mk
index 86a4f7d..7cfd28c 100644
--- a/Makefile-dsk.mk
+++ b/Makefile-dsk.mk
@@ -1,14 +1,21 @@
-DSK = cc65-Chess.dsk
-
-# For this one, see https://applecommander.github.io/
-AC ?= ac.jar
-
-REMOVES += $(DSK)
-
-.PHONY: dsk
-dsk: $(DSK)
-
-$(DSK): cc65-Chess.apple2
-	copy apple2\template.dsk $@
-	java -jar $(AC) -p  $@ chess.system sys < $(shell cl65 --print-target-path)\apple2\util\loader.system
-	java -jar $(AC) -as $@ chess        bin < cc65-Chess.apple2
+DSK = cc65-Chess.dsk
+
+# For this one, see https://applecommander.github.io/
+AC ?= ac.jar
+
+# Unix or Windows
+ifeq ($(shell echo),)
+	CP = cp $1
+else
+	CP = copy $(subst /,\,$1)
+endif
+
+REMOVES += $(DSK)
+
+.PHONY: dsk
+dsk: $(DSK)
+
+$(DSK): cc65-Chess.apple2
+	$(call CP, apple2/template.dsk $@)
+	java -jar $(AC) -p  $@ chess.system sys < $(shell cl65 --print-target-path)/apple2/util/loader.system
+	java -jar $(AC) -as $@ chess        bin < cc65-Chess.apple2