cd build; jar cvf ../$@ .
# -O3 is required; otherwise the poor AVR can't keep up with us!
-avrdrone.hex:
- avr-gcc -O3 -mmcu=at94k src/edu/berkeley/obits/device/atmel/AvrDrone.c
+avrdrone.hex: src/edu/berkeley/obits/device/atmel/AvrDrone.c
+ avr-gcc -O3 -mmcu=at94k $<
avr-objcopy -O ihex a.out $@