Founded a fitness app ~1 year ago and built the first version in react native. After a lot of iterations, we finally have signs of PMF: user base growing by 25% monthly, with a lot of stickiness.Moving to native iOS app starting in 2 weeks.  Had a CTO lined up, but they took a job at big tech at the last minute. We are raising our seed in 4-5 weeks and are aggressively recruiting to fill the role.Experience building scalable backends for video  & streaming content is important.Our existing team is strong on the business side, both in the fitness sector and tech.  Our COO has been a professional athlete + owner of a chain of gyms for the past 15 years.  Our CPO is an ex-ClassPass product person. I am a serial entrepreneur coming from another tech sector. Pre-seed funding came half from NYC area gym owners who wanted to see this happen (they want a ClassPass-killer) and half from a bunch of people at a hedge fund investing in a personal capacity.Again, we have good PMF indicators and have the product strategy worked out for the next version of the app.  We have a junior iOS engineer who is starting at the end of this month to build this next version, with guidance from a senior mentor.Casting a wide net to solve this very important problem.