It's our first anniversary and—almost 50 episodes in—Jacob Goldstein checks in with three past guests. 
Drone delivery guy Keenan Wyrobek thinks he has solved a big problem holding back commercial drone delivery in America. Fruit-ripening maven Katherine Sizov is figuring out bananas. And Glenn Kelman of Redfin has some deep insights from a tough year in the real estate business.
*The problems in real estate weren't so much solved as left behind.