Swift wrote the lyrics to producer Aaron Dessner's dreamy acoustic instrumentation. The National band member originally penned the music for his Big Red Machine project with Justin Veron, but Swift heard it and came up with "Right Where You Left Me" and "Happiness
" literally days before the completion of Evermore
. "That is a little bit how she works," Dessner told Rolling Stone
. "She writes a lot of songs, and then at the very end she sometimes writes one or two more, and they often are important ones."