Zoe Kazan, who plays Ruby, also wrote the screenplay for "Ruby Sparks". Zoe's grandfather is Elia Kazan, who directed "On the Waterfront (1954)". Her mother, Robin Swicord, wrote the screenplay for "The Curious Case of Benjamin Button (2008)". Her father, Nicholas Kazan wrote the screenplay for "Reversal of Fortune (1990)".
The eccentric house that Calvin's mother lives in is supposed to be in Big Sur, but it's actually a house in the Hollywood Hills that once belonged to Sid Krofft, of "Sid & Marty Krofft" fame. Much of the dialogue in that scene describing material details about the house was written on the spot based on the actual owner's tour of the place on the day of the shoot.