Publishing Go Packages

A reusable package becomes available to other projects when its module source, import path, API and version tags are accessible.

Give the module a stable path that corresponds to a reachable repository, write documentation for exported identifiers and provide tests. Git semantic version tags such as v1.0.0 identify module releases. For major versions v2 and later, most module paths need a matching /v2 suffix.

Publishing often means pushing source and tags to a public version-control host; the public Go module proxy can discover them when clients request the module. Private module setups need additional authentication and environment configuration.

Follow this diagram before executing the example. Check where a value or decision changes what runs next.

Read the official Publishing a module guide before releasing real code.

This example is a complete program. Save it as main.go or paste it into the Go Playground.

Go code

package main

import "fmt"

// Greeting represents a small exported API in a reusable package.
func Greeting(name string) string { return "Hello, " + name }
func main()                       { fmt.Println(Greeting("developer")) }

Output

Hello, developer

The program exercises a small exported function as a consumer would. To publish it as a library, move the function into a non-main package and give the module a reachable path.

• Semantic version tags apply to modules, not to individual .go files.
• Public releases should not contain secrets or internal credentials.

Draft documentation for Greeting and plan a first module tag. Verify the package with go test ./....

Tip: Edit the example above, predict the output, and run the modified code to test your reasoning.

You have practiced Publishing Go Packages in a small, self-contained program. The important habit is to predict what runs, inspect the actual output and distinguish the language rule from the particular example.

Before continuing, make sure you can explain the program to someone who has not seen it, including the line that changes its result.