I'm 80 years old and somehow I woke up in my 25 year old body for just 1 day. I catch my reflection in the bathroom mirror. No deep lines. No gray hair. Only my younger face, staring back at me. For 24 hours I could do anything. Call the people I'd lost. Say the things I never said. Watch a sunset without looking at my phone. So I opened up my laptop, forked GStack, and applied to YCombinator.