Almost 2 months ago, we have received an issue that the protocol implementation is sometimes lost in umbrellas. Others have echoed the issue but we are unable to reproduce it. The issue report can be found here: https://github.com/elixir-lang/elixir/issues/5987
If someone is running into this issue and can consistently reproduce it, please let us know. Given the annoyance of this issue, if it is necessary for one of the core team members to access a private repository, we would be willing to do that exceptionally in this case.