| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| errors | Package errors implements functions to manipulate errors. |
| github.com/google/trillian/util/clock | Package clock contains time utilities, and types that allow mocking system time in tests. |
| github.com/google/trillian/util/election2 | Package election2 provides master election tools, and interfaces for plugging in a custom underlying mechanism. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| testing | Package testing provides support for automated testing of Go packages. |
| time | Package time provides functionality for measuring and displaying time. |