One other thing to think about would be intangibles the startups can offer vs open source:
* how good are you at self-motivating
* what chance is there of being mentored at the start up?
* will the CEO provide a good reference later one: a human reference likely beats pointing out the open source contributions in many jobs in the future
If you are going to work for free anyway on open source then make sure you have the dedication to actually do it.
Being more directly accountable to someone may be a benefit.
* how good are you at self-motivating * what chance is there of being mentored at the start up? * will the CEO provide a good reference later one: a human reference likely beats pointing out the open source contributions in many jobs in the future
If you are going to work for free anyway on open source then make sure you have the dedication to actually do it.
Being more directly accountable to someone may be a benefit.
Good luck ... it's a tough call!