What is a pkg folder?

Answered by Phillip Nicastro

The pkg folder in Go is an essential part of the Go build system. It serves as a location to store compiled package objects that are generated during the build process. These package objects are created from the Go source code packages located in the src directory.

When you compile a Go program, each package is compiled separately into a package object. These package objects contain the compiled bytecode and metadata for the package. By separating the compilation process, Go allows for efficient recompilation and reuse of package objects.

The pkg folder is structured based on the target operating system and architecture. Inside the pkg directory, you will find subdirectories named after the target operating system and architecture, such as linux_amd64, darwin_arm64, or windows_386. These subdirectories contain the compiled package objects specific to that particular platform.

One of the advantages of the pkg directory is that it allows for faster builds. Once a package is compiled, the resulting package object can be reused across different executables that depend on that package. This means that you don’t need to recompile the package every time you build a new executable. Instead, the already compiled package object can be linked into the new executable, saving time and resources.

Additionally, the pkg directory helps in managing dependencies. When you import a package in your Go code, the build system looks for the package object in the pkg directory. If the package object is not found, the build system will compile the necessary package and store it in the appropriate subdirectory of the pkg directory.

The pkg directory plays a crucial role in the build process of Go programs. It allows for efficient recompilation and reuse of package objects, leading to faster builds and better dependency management. Understanding the purpose and structure of the pkg folder is essential for Go developers to optimize their build workflow and manage dependencies effectively.

To summarize, the pkg folder in Go is a location to store compiled package objects generated during the build process. It allows for efficient recompilation and reuse of package objects, resulting in faster builds and better dependency management.