I have a brand new, mostly solo startup. The good news is that there is actually some momentum occurring - which means I need to start blogging under my own name, going to networking events and generally becoming the voice and face of my company. My startup is self funded & shoestring; I'm a regular person with kiddos and a mortgage, so must keep that day job. While my startup in no way competes with my day job (service, product-wise, and I never use company time to do the startup, obviously) - my boss would be happy at all about this situation. The boss might decide to do the exact same thing, as he has easy access to great developers. Any advice on publicizing while in stealth mode?
First, I'm a dad and an entrepreneur. Kudos to you! It's a big deal doing this with kiddos.
Second, it's hard to say entirely without knowing more details. But, I won an entire startup competition without my day job knowing (six months). It was completely legal, I just didn't want the hassle of talking through why I was doing something on the side. If you're no legally allowed to, that's a different ball game.
Third, for what it's worth, online customers may not need to know much about *you* for quite some time. You can attend physical events without having to put your name on your site or social profiles just yet. You can blog as the company and fill your 'about' page with company mission and vision info. If the product isn't a consultancy, podcast, etc. you might be able to stay anonymous for longer than you think.
Fourth, there is always a fear someone else could steal the idea. It doesn't happen often though!
Fifth, I would advise waiting until you absolutely *have* to say something - preferably when the company is at a point you can jump ship.
Sixth, keep all your personal files off your work computers. Or, use a password protected partition for all those files. It's just a smart way to operate with this stuff.
I hope that helps! If you want to chat about it let me know. I'm easy to find on Twitter if a phone call doesn't make sense.