"Think about why you want one." So many requests for technical co-founder seem to boil down to "I had this awesome idea for a fully sick app bro, I just need someone to do some coding and we'll make millions!" Or in other words, "build my dream for free and I'll be your boss and you can keep half the profits maybe". Sounds great.

Frankly I find the "ideas guys" to be insulting, as if they think that having technical ability somehow means you're automatically bereft of imagination, just sitting around waiting for someone "creative" to show up and "let you in on their big idea". Most people with serious technical chops develop them in pursuit of some other goal.

Rant aside, I guess I should flip this into some kind of advice. They need to bring something serious to the table. Like, for example, one or more of:

(a) A top tier domain expert in the domain you're targeting, with deep insight into stellar industry contacts

(b) A business wizard with the ability to raise serious funding on good terms, negotiate contracts and supply agreements, identify optimal pricing structures

(c) A management wizard with the soft skills required to recruit a startup's worth of unique characters and keep them working effectively together

(d) Someone who's loaded and bankrolling the gig, for which you will be paid a competitive wage plus receive substantial equity