Can you put the hard drive from the extra laptop inside the Mac? If so, grab your code (as already discussed on other comments), and put that disk in the mac.

Can you put the hard drive from the extra laptop inside the Mac? If so, grab your code (as already discussed on other comments), and put that disk in the mac. Boot with command+r pressed, and you'll be able to install OS X onto the new drive. Slightly off-topic: Since you specifically need OS X, Do you do iOS development?