How much sharing is too much sharing when you build in public?

I think it depends on how far you are along in the build and if theres any advantage to being in the marketplace. I think once you have a production ready product it makes sense to go live because - as Braden said - ideas can be stolen. So if you can gain first mover advantage and get some marketshare that way - why not capture that audience while you can.

The reality is, ideas can be stolen no matter the stage of the company, unless the tech is so novel it can be patented (even then you're not fully protected). If the idea is great, then expect someone to copy you. What really matters is execution. Focus on how you can out-execute and out-maneuver your competition, even if that competition doesn't yet exist. Also, reframe sharing to "gathering feedback". Start with those you trust, then as you get further down the line to making it a reality, share it with potential users in the form of a prototype. Sharing is a superpower, not a weakness!