| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| github.com/golang/glog | Package glog implements logging analogous to the Google-internal C++ INFO/ERROR/V setup. |
| github.com/google/trillian/util/clock | Package clock contains time utilities, and types that allow mocking system time in tests. |
| google.golang.org/grpc | Package grpc implements an RPC system called gRPC. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| time | Package time provides functionality for measuring and displaying time. |