Disclosure: I work at Google, but not on Copybara.
I've seen Copybara used at Google in both directions: for some projects, the internal repo is the authoritative one, and for others, the external repo is authoritative.
Copybara is not prescriptive, you can go in either direction.
I've seen Copybara used at Google in both directions: for some projects, the internal repo is the authoritative one, and for others, the external repo is authoritative.
Copybara is not prescriptive, you can go in either direction.