Almost all variables are uint8_t except for the array holding reference values for analog read (one-pin membrane keypad values up to a value of 1023, so it had to be of type int. Sorry I don't have the code at the moment but it is about 1200 bytes and I am sure it can be squeezed downto 1024 bytes... But yeah, my noobish assembly always produces at least a few bytes more than GCC compiler 
Sketch is for electronic lock, with 7-seg display, keypad, servo, few capacitors and resistors, switch, and one mosfet. It auto-shuts down completely after few seconds of inactivity in order to save battery.
Now, this int array of 17 elements is taking up too much of valuable dynamic memory. ATtiny13 has only 64 bytes.