My understanding was that a rocket is developed around its engines. What engines are you designing on top of? Are you only developing the second stage? If so,

My understanding was that a rocket is developed around its engines. What engines are you designing on top of? Are you only developing the second stage? If so, what first stage are you planning to launch off of? What is your target payload mass to LEO? And, well, where does your company fit in a post-SpaceX Starship orbital economy?