| cmp | Package cmp provides types and functions related to comparing ordered values. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| maps | Package maps defines various functions useful with maps of any type. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| path/filepath | Package filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths. |
| slices | Package slices defines various functions useful with slices of any type. |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |