You should know that a startup does not mean you do all the time only the things you like. Besides writing code (which is the best part :) ) sometimes you need to do customer support, boring paper-work, leave the best party to restart your servers, even clean your office by yourself. And may other things I can not remember right know...
This isn't the first project I've done. I did a project while I was learning the language and honestly I just wanted to go to sleep every night at 3am. It wasn't the fun that even got me through coding the damn thing. Fun isn't necessarily the reason I push myself through the work. So I more than know there are tough challenges and unpleasent experiences to come. It's really the satisfaction everytime I overcome a challenge and the results that lure me to the end.
