If my product's target market is software developers (that could build a competing product) how can I get feedback while protecting IP?

Hey,
1. If your product/software requires above 50 hours of programming then you don't need to worry about anyone 'stealing' your idea. This rarely happens.
2. Ideas are a dime a dozen. The difficult part is the execution (and marketing).
3. If your product/service can be created in a number of hours, you might want to reconsider as this means that the entry barrier/uniqueness is very low and this will be a problem for investors.
The above is a generalization because I don't know exactly which product you have so I can't be 100% sure.

Good luck

1) Hire people smart enough to do the work.

2) Pay them out of profits.

This way they'll keep quiet, because if they speak, they lose money.

3) Also know, your idea isn't new... "There is no new thing under the sun."

In fact, the worst ideas are anything new.

Always do something... that's already been done... either do it better or do some "seemingly new spin".

If it was easy, they would have already done it. For the most part, I would not be too concerned about your IP. It takes so much time, effort, money, the research you want to do etc, that it is not very likely anyone will take your idea and run with it. Of course, this answer is with no knowledge of what you want to build, and yes some concepts could be easy to replicate. But competition is a good thing! You just have to better, faster, know your customer and deliver quality. With your current thinking, you'll face the same dilemma when you (beta) launch.