The first version is not going to be the final remember, and it will very likely a lot of the code be rewritten. Push off as many features to post launch. Don't just choose a cool new programming language just to learn it for your startup. Choose what you're dangerous enough and comfortable to launch quickly. The other thing is also, is very easy to build MVPs very quickly by using third party frameworks and API tools.
YC Group Partner Diana Hu was the CTO of her YC startup Escher Reality, which was acquired by Niantic (makers of Pokemon Go). She shares her advice for being a technical founder at the earliest stages - including topics like how to ship an MVP fast, how to deal with technology choices and technical debt, and how and when to hire an engineering team.
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