I have spent multiple peruods of my career where I was either self employed or unemployed to spend time working on my own thing. This never seemed to have an impact on whether I could land interviews. Assuming you are in skme form of tech role, chances are you aren't doing any damage to your career whatsoever by going for entrepreneurship. Why would a field heavily founded on entrepreneurship punish entrepreneurs? If anything, some companies want to hire people who were entrepreneurs even if their idea failed.