You are probably right. The Instagram Engineering blog [0] points to the Fabric documentation on Read the Docs [1] which is empty.
"Read the docs" links to the GitHub repo [2] but it's 404 and even the GitHub organization zwsyff888 is gone.
[0] https://instagram-engineering.com/what-powers-instagram-hund...
[1] https://fabric.readthedocs.io
[2] https://github.com/zwsyff888/fabric