| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| google.golang.org/grpc | Package grpc implements an RPC system called gRPC. |
| google.golang.org/grpc/internal | Package internal contains gRPC-internal code, to avoid polluting the godoc of the top-level grpc package. |
| google.golang.org/grpc/resolver | Package resolver defines APIs for name resolution in gRPC. |
| google.golang.org/grpc/serviceconfig | Package serviceconfig defines types and methods for operating on gRPC service configs. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |