| crypto | Package crypto collects common cryptographic constants. |
| crypto/sha256 | Package sha256 implements the SHA224 and SHA256 hash algorithms as defined in FIPS 180-4. |
| encoding/base64 | Package base64 implements base64 encoding as specified by RFC 4648. |
| encoding/hex | Package hex implements hexadecimal encoding and decoding. |
| io | Package io provides basic interfaces to I/O primitives. |
| path | Package path implements utility routines for manipulating slash-separated paths. |
| path/filepath | Package filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| testing | Package testing provides support for automated testing of Go packages. |