| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| github.com/containerd/errdefs | Package errdefs defines the common errors used throughout containerd packages. |
| github.com/containerd/log | Package log provides types and functions related to logging, passing loggers through a context, and attaching context to the logger. |
| io | Package io provides basic interfaces to I/O primitives. |
| regexp | Package regexp implements regular expression search. |
| unicode | Package unicode provides data and functions to test some properties of Unicode code points. |
| unicode/utf8 | Package utf8 implements functions and constants to support text encoded in UTF-8. |