You could recruit some first year undergrads at a university. Offer to mentor them and teach them some programming as they work on your project.
Another option is to participate in a weekend hackathon. At the hackathon I went to, people presented their project ideas and others could join them. If your idea is interesting, you could attract some interested developers to work on your project for a couple of days. If they like it, they may keep working with you after the hackathon.