| bytes | Package bytes implements functions for the manipulation of byte slices. |
| cmd/go/internal/cfg | Package cfg holds configuration shared by multiple parts of the go command. |
| cmd/go/internal/str | Package str provides string manipulation utilities. |
| crypto/sha256 | Package sha256 implements the SHA224 and SHA256 hash algorithms as defined in FIPS 180-4. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| io | Package io provides basic interfaces to I/O primitives. |
| io/ioutil | Package ioutil implements some I/O utility functions. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| os/exec | Package exec runs external commands. |
| path/filepath | Package filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| time | Package time provides functionality for measuring and displaying time. |