well, thats because the rules are for both encrypting and decrypting. %.enc:% %:%.enc In one file. So enc -> file -> enc. You can split them out, so en

well, thats because the rules are for both encrypting and decrypting. %.enc:% %:%.enc In one file. So enc -> file -> enc. You can split them out, so encrypt in one makefile and decrypt in another. make -f Encrypt foo.enc make -f Decrypt foo but thats been bugging me as well, so here is an all in one $E: openssl aes-256-cbc -a -salt -in $(patsubst %.enc,%,$@) -out $@ $D: openssl aes-256-cbc -d -a -in $@.enc -out $@ make E=foo.enc make D=foo use make at your own peril :)