An option for #1175:
0$ git fetch origin pull/1287/head
1$ git archive --output=libsecp256k1-PR1287.tar.gz FETCH_HEAD
2$ sha256sum libsecp256k1-PR1287.tar.gz
36e6fd21afd935e572b138258f782fed60bb11fa88aa51a9866f10cca5d25c39c libsecp256k1-PR1287.tar.gz
4$ git archive --output=libsecp256k1-PR1287.zip FETCH_HEAD
5$ sha256sum libsecp256k1-PR1287.zip
6e108fc4902502640eee2cf4bb69501a494904c4dcd0763c072cc4acaed565861 libsecp256k1-PR1287.zip