[kenshaw]

In proto3 all fields are optional. As such, I don't see the need for "oneof" since you should check in business logic whether or not the field is there. By using "oneof" you are declaring two different types can be the same name. It's a philosophical argument that you're free to disagree with.

[joshuamorton]

In good proto2, all fields are optional, that doesn't negate the uses of one of, which provide compile time validation instead of runtime, which is the important part.

[kenshaw]

Yes, I understand how this would be done. It's a design philosophy. If you'd like Gunk to support "oneof", we're open to Pull Requests!