Your question is clear and understandable, but you either need to pay for the services, or give away equity - talented and trustworthy people won't work for free - nor should they.
The only question that remains is how can you develop the platform while paying less or giving away less equity.
Answers:
1. found a co-founder whose only role is the development of the platform for a relatively low amount of equity and no voting/management rights.
2. Pay beginner programmers who are looking to gain experience (cheaper costs).
3. I know a development company that might be willing to create the platform for you in exchange for a relatively low amount of equity. Additionally, you can draft the agreement so that the equity is given in stages - based on the work that you do.
the only costs that you would have is for drafting the legal contract because they insist on having their lawyer do the legal work and he charges payment (half upfront and half after the work is complete). The programming company also offers a "buy-back" option - this means that if within x amount of months you want to buy back your shares, you can do so, but at double the value of the programming costs.
Let me know if this is relevant.
Good luck
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