Ask HN: What's the right structure for geeks starting a software project?

I’ve been doing solo consulting work and development under my LLC for a while (in the SF Bay Area).

Recently, a few ex-coworkers have expressed interest in working on one of my projects with me.

I’ve been wondering what the right structure is to harness work from a bunch of geeks with various commitment levels (some would be full time, others part time), in order to ensure that:

- the structure/entity is neither expensive nor paperwork-intensive (not sure it makes sense to spend $$ on a new C-corp before we can see traction in the market)

- the work from each of us is assigned to “the entity” (to prevent problems later on with early member claims)

- we aren’t transgressing any labor law (min wage, etc) while we work “for free”

- we can have a reasonably clean transition into something more mature (C-Corp?) should we reach some success milestone

- we have liability protection

This is a group of people who have worked well together in the past and would likely work on another project together even if the first one failed, but by the same token, life changes happen, and it’s also very possible that some team member(s) will decide to go off and do something else.

Ideally there would be enough written down for people to know what to expect if/when we kick it into high gear, as I want to make sure that people get rewarded fairly for the sweat they put in, and to minimize surprises/disappointments.

I do struggle to come up with the right concept to express a promise in case of success, especially when there is such a disparity in commitment levels. Is it expressed in “x% of the company per hour of work”? Is it right to look at it from a time investment perspective?

Surely many ventures start with a bunch of geeks working out in a “garage” with no pay, right? How do people typically do this?