Make sure to define tools and ways of working. Believe me, do this sooner rather than later. If you are like me and you like documenting things (i.e. hours spent on tasks or projects, notes during calls, etc) try to do that in a centralised place.
Founders especially have very strong opinions on what and how the product should be. As they should. They are founders. It's their role to set the vision and have the drive to achieve that. You are just a medium to get there. Your role is to leverage your expertise to design and build something awesome for them. Just keep in mind that, as much as you want to put your heart and soul into your work, your baby will also be the studio, not its deliverables.
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