diff --git a/Makefile b/Makefile
index 15cd6c5..e8559da 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@ CFLAGS=--std=c99 -O3 -Wall -Werror -Wextra -pedantic
 
 .PHONY: clean install uninstall test
 
-${TARGET}: main.c
+${TARGET}: ${TARGET}.c
 	${CC} ${CFLAGS} ${LDFLAGS} $< -o $@
 
 clean:
diff --git a/main.c b/kwh-cost.c
similarity index 100%
rename from main.c
rename to kwh-cost.c