I became a co-founder after one phone call and a beer. I had never met my co-founder before that night.

How is it working out for you?

Good so far. Still just a side project with zero revenue (we both have day jobs), but it’s been a blast.

We haven’t had a major disagreement yet. I suppose that’s when I’ll find out if I was foolish or not…

You better make it all official with contracts that give equity based on time spent or include clauses that remove equity from a founder if he leaves or doesn't fulfill his duties. You don't want to be doing all the work while a guy who owns 50% of the company has left to do his own thing.

I also just became co-founder of a startup after just a few months of "interning" for a friend. Seems so quick but so far so good! Sometimes we just stumble into this stuff I suppose! Good luck!