As you already know in a startup one have to wear multiple hats. In my startup journey from the past 9 years have been an entrepreneur, programmer and a designer but from the past 5 years, I have been working more on the business & marketing side.
Been working on my startup Get Started (https://getstarted.in) for the last few months. Previously was with Piggy (Y Combinator S17) and ApnaComplex as Head of Marketing, ex-Growth Hacker at CitrusPay / PayU and before that at Zolo as Marketing Head and in Momoe as Community Engagement Head.
You can find more details about me here: https://linkedin.com/in/vivekrp and http://vivekrp.com
[ my public key: https://keybase.io/vivekrp; my proof: https://keybase.io/vivekrp/sigs/ma2lWQ2BSwc8o6ywvTlyfMHv4KYQUaGXd9LQRGRTm1o ]