For most programmers, this is a red flag. It often means that the owner of the company either doesn't believe in their idea enough to risk their own assets, or couldn't find any investors that believe in their idea enough to lend them the money. Many entrepreneurial programmers have more than enough ideas that interest them to keep themselves busy during any free time they have, so the only reason to work for someone else is for the money or because they don't want to manage the business side. And the non-entrepreneurial programmers wouldn't want to take the risk.
There are, of course, needles in the haystacks. But these things usually work better when two people collaborate from the beginning and already have a pre-existing relationship. At this point, your best option is likely to find a bank (I'd suggest a credit union or other small bank) that is willing to lend you the funds, secured with a personal guarantee of some sort.
Note that this isn't to say you shouldn't offer equity to your first developer, but I'd consider an employee stock purchasing plan rather than giving them the shares outright. This encourages them to become investors without a confrontational entitlement mentality. I'd also consider giving them a portion of the bonus in equity and base the bonus on major milestones.
Working for equity is taking a double risk:
You, as owner, take only one risk part and the developer both. So, why should anybody work for equity only?
It can work only if the developer have major equity share and is a equal owner as you are.
It would be. You'd need to find a developer who doesn't need an income to survive and someone who has faith in your idea.... and finds your idea worth more than their time otherwise.
Being a programmer myself, I have to admit, I'm intrigued.
Bring proof that your 'idea' will fly by being able to show that you talked to customers, that you learned in the field, iterated your idea, and ideally be able to show some documented commitment from future clients. Think Lean Start-up Methodology. If you can show that, rather than 'just' an idea, you will eventually be able to convince someone with the skills you are looking for (programmer, designer, marketer...) to want to join you.
And broaden your search for a co-founder including all sorts of channels, off-line and on-line.
I do not think that you are best with discussing it with your programmer first. If I were the programmer, I would not be willing to do a project that is unsure of its future and I think that you have to consider the outside point of view. Programmers code to earn and nothing more. If you will find someone who would be willing with that option, then good for you. But I think that would be a tougher job than you imagined.
Best way to get a programmer in for equity is to get them younger when they just want to cut their teeth on something. Sophomore or Junior in college who knows enough about programming but needs some help harnessing it is your best bet.
But to get a veteran programmer who is tried and true... they (I) would need to be 100% sold on the idea being gold. Or need some $ and Equity on the line or be matched with some marketing funds. Say I valued my initial development time to get the product to v1 at $50,000. I would want to see $50,000 or so in the bank to be spent on marketing/sales.