What I am certain of, except where marked (?):
* It was on AO3.
* Pairing is Clint/Darcy.
* At the beginning of the fanfic, Clint is in an interrogation room (?) with Fury.
* Clint intimidated the manager of the local bar in Puente Antiguo into letting him play a set.
* Clint has two guitars (?) that he has has for years, one of which has been set up to let him shoot arrows. The first one he got had a name that started with a p or b.
* Darcy persuades him to record some of his own music to be released under a stage name, which has something to do with a bird.
* He doesn't realize his work is popular until he is out somewhere public and he hears one of his songs.
* He ends up playing and revealing his identity at a Stark Expo (?) when the Big Country Artist who is scheduled can't get there.