| cmd/go/internal/base | Package base defines shared basic pieces of the go command, in particular logging and the Command structure. |
| cmd/go/internal/cfg | Package cfg holds configuration shared by multiple parts of the go command. |
| cmd/go/internal/gover | Package gover implements support for Go toolchain versions like 1.21.0 and 1.21rc1. |
| cmd/go/internal/modfetch | |
| cmd/go/internal/modload | |
| cmd/go/internal/run | Package run implements the “go run” command. |
| cmd/go/internal/work | |
| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| errors | Package errors implements functions to manipulate errors. |
| flag | Package flag implements command-line flag parsing. |
| 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/module | Package module defines the module.Version type along with support code. |
| internal/godebug | Package godebug makes the settings in the $GODEBUG environment variable available to other packages. |
| internal/syscall/unix | |
| io/fs | Package fs defines basic interfaces to a file system. |
| log | Package log implements a simple logging package. |
| 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. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| 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. |
| syscall | Package syscall contains an interface to the low-level operating system primitives. |