The film was shot in February and April of 2018. It spent two years in post production.
On the day that the lake scene was filmed at Pine Lake Park in San Francisco, the cast and crew ran into Mythbuster Adam Savage who was walking his dog at the park.
All of the driving shots required a special car mount that suction-cupped onto the hood of the Minnie Cooper. Justin Teixeira, Jasper Salomon, and Mason McNicoll Bosworth drove the car themselves and shot the scenes alone, however, the sound guy was hidden in the trunk.
Noah Namgoong wrote the poem that Ernest reads to his mother. Namgoong cited the short story "Hills Like White Elephants" by Ernest Hemingway as inspiration for the poem and the film.
The character James is known for his eccentric haircut. This was completely the design of actor Jasper Salomon. He asked Noah Namgoong what kind of haircut his character should have, and Namgoong said, "whatever you want". The look we see is what Salomon came up with.