Most of my clients are non-technical founders. My role is generally that of an early stage CTO.

I do pretty much everything on the technical side to get the product off the ground and scale it, from wireframing, to writing the code, and ultimately helping build the team or onboarding a FT CTO or VP Eng. My period of involvement varies from about 6 months (generally takes at least this long to find a good CTO candidate) to 4-5 years, at which point I'm usually leading the tech team.