| bytes | Package bytes implements functions for the manipulation of byte slices. |
| cmd/go/internal/base | Package base defines shared basic pieces of the go command, in particular logging and the Command structure. |
| cmd/go/internal/cache | Package cache implements a build artifact cache. |
| cmd/go/internal/cfg | Package cfg holds configuration shared by multiple parts of the go command. |
| cmd/go/internal/imports | |
| cmd/go/internal/load | Package load loads packages. |
| cmd/go/internal/lockedfile | Package lockedfile creates and manipulates files whose contents should only change atomically. |
| cmd/go/internal/modconv | |
| cmd/go/internal/modfetch | |
| cmd/go/internal/modfetch/codehost | Package codehost defines the interface implemented by a code hosting source, along with support code for use by implementations. |
| cmd/go/internal/modinfo | |
| cmd/go/internal/mvs | Package mvs implements Minimal Version Selection. |
| cmd/go/internal/par | |
| cmd/go/internal/search | |
| cmd/go/internal/str | Package str provides string manipulation utilities. |
| encoding/hex | Package hex implements hexadecimal encoding and decoding. |
| encoding/json | Package json implements encoding and decoding of JSON as defined in RFC 7159. |
| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| go/build | Package build gathers information about Go packages. |
| golang.org/x/mod/modfile | Package modfile implements a parser and formatter for go.mod files. |
| golang.org/x/mod/module | Package module defines the module.Version type along with support code. |
| golang.org/x/mod/semver | Package semver implements comparison of semantic version strings. |
| internal/goroot | |
| internal/lazyregexp | Package lazyregexp is a thin wrapper over regexp, allowing the use of global regexp variables without forcing them to be compiled at init. |
| io/ioutil | Package ioutil implements some I/O utility functions. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| 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/debug | Package debug contains facilities for programs to debug themselves while they are running. |
| sort | Package sort provides primitives for sorting slices and user-defined collections. |
| 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. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| syscall | Package syscall contains an interface to the low-level operating system primitives. |
| time | Package time provides functionality for measuring and displaying time. |