I'll have to echo Humberto Valle when he asks why you need a resume at all when you are starting a startup. This doesn't really make sense and, from an employers perspective, a red flag that says at best you are temporary, at worst you are distracted. I would take a hard look at what you are doing and decide if you want to start something or work for someone. Then, read Humberto Valle's advice on focusing on the outcomes you've achieved while helping with the startup and move on.

Startups aren't part time IMO.