Questions about team composition and team effectiveness are on topic here. However, questions about business plans and startup funding are out of scope for a site about the practice and profession of project management.
With that in mind, I will address myself solely to the project management perspective here. I'll cover why you need the project management perspective, and highlight the boundaries of your responsibilities within that perspective.
The X in your X/Y problem is that you apparently have responsibility for delivering a product and building a team, but lack the resources (and likely the authority) to do it effectively. Responsibility without authority or resources is a no-op. You will likely need to reframe your role, and involve the rest of the founders in addressing your various resource shortages.
Understanding Why You Need a PM Perspective
As a gross oversimplification, the CTO role in a startup wears many hats, some of which fall within the realms of project and product management. These often include:
- Providing a product vision.
- Providing a roadmap for realizing the vision.
- Hands-on product development work.
- Building a technical organization to develop and support the product.
A Venn diagram of CTO vs. PM in smaller organizations will have a lot of overlap, especially in the following roles:
- Product Owner
- Project Manager or Scrum Master
- Business Analyst
- Product Developer
- Quality Assurance
- Line Manager
- The list goes on...
Functionally, an early-stage CTO needs to be focused on getting a product to market. The project management perspective is all about how you plan to turn the product vision into a salable product through controlled development and delivery. The project plan should strive to deliver a predictable development cadence that provides confidence that development milestones and delivery targets can be met.
Capitalizing a Project: Out of Scope for PM
You need skills, materials, and other resources to deliver on your project plan. That generally means hiring people as employees or outsourcing work, and building the tool chain and infrastructure you need to build your prototype, proof of concept, or initial product.
From a project management perspective, it is the job of senior management to ensure that the project is properly funded. The role of project manager sometimes comes with budgetary authority (although more often it comes with responsibility without authority). However, you will not find fundraising or "getting people to work for free" in the PMBOK. Lining up investment dollars is outside the role of project management, so in your project management role your responsibility is to notify the rest of the C-suite of budget or resource constraints.
From a project management perspective, trying to build a product to a predictable schedule with zero budget is kind of like pushing a pea up Mount Vesuvius with your nose. You simply can't reliably deliver without dedicated (pronounced "paid") resources.
Volunteers (and unpaid "employees" with unvested stock are essentially volunteers) can't be counted on individually over the long haul. Even open-source projects with a critical mass of volunteers don't usually target fixed release cycles based on anything other than time-boxing. From a project management perspective, your job is to determine what work needs to be done, and then make that information visible to the project sponsor so it can be properly funded. Getting blood from a stone may be an expectation in your organization, but it is not how successful project management works.
Investing in a company—and make no mistake, equity-only plays or fully-deferred compensation are investments rather than employment arrangements—are things that founders or business owners do, but employees (by definition) do not. If you're asking how to build a team of investors, that's out of scope for this site. If you want to build a development team, though, you need to have a budget greater than zero, and then build the best cross-functional team you can within that budget.
If you lack the budget or effective incentives to build the team you need, then the C-suite collectively owns the problem. Tell the CEO and CFO what you need to build the product (including essential people and skills), and propose a realistic budget for it. If the business plan doesn't currently address the capital and operating costs needed to get to market, or at least your company's next round of funding, then it's your job to raise the issue. It's then the C-suite's job to make operational decisions based on that information.
Who Owns the Problem?
The C-suite owns the strategic plan and full operational authority. To the extent that you are considered a member of the C-suite, you share that responsibility with your peers. However, you don't own it alone, and you definitely don't own it from a project management perspective.
The project management perspective is that you are responsible for planning and controlling the budget, scope, and schedule of the project. Anything outside your span of control must be hoisted up the organizational flagpole to see who salutes.
Ultimately, the CEO and (if you have one) the Board of Directors own the business plan, the budget, and the success or failure of the venture. Either get them engaged with the problem, or come to terms with the fact that you've "invested" in a company without a viable business plan and act accordingly.