"One thing to keep in mind, is if the 2 co-founders see you as just a code monkey, chances are they don't understand how fundamental you will become to the success of the product. This means if the product becomes wildly successful you'll have an enormous amount of leverage down the road to renegotiate your compensation."
If they view this guy as a code monkey now, when he comes in to renegotiate they'll tell him to take a flying leap on the assumption they can just hire some random off craigslist to replace him. Assuming he's a good developer this is of course not true, but they won't know it. Eventually they will realize the terrible mistake they made when the replacement screws the pooch, but that's like 6 months later after the original developer is long gone.
If they're just becoming successful they probably won't want to rock the boat too much by firing their first employee. You could be right though if they're real douches.
If they view this guy as a code monkey now, when he comes in to renegotiate they'll tell him to take a flying leap on the assumption they can just hire some random off craigslist to replace him. Assuming he's a good developer this is of course not true, but they won't know it. Eventually they will realize the terrible mistake they made when the replacement screws the pooch, but that's like 6 months later after the original developer is long gone.