The business has a really solid business model, a working prototype built by a contractor, the attention of local angel investors, etc. It's a really good fit.

The current founder needs a technical cofounder to help him raise his Series A funding, and at this point, it's looking like I'm that guy.

We've gotten to the point where we need to discuss how much equity I'll have in the company by joining as a cofounder, how it will vest over time, etc. The problem is that I don't know how this should work. My previous startup experience has always seen equity evenly split among all of the cofounders, but I don't think it's appropriate for me to ask that in this case because so much of the work is already done.

Has anyone else been in a situation like this? How did you handle it? Any suggestions for me?