What is the Purpose of Docker Buildx?

Docker is a well-known tool for building and executing packaged applications. Docker images are the basic element of Docker. However, building images for different platforms can be challenging, especially if the user wants to use the same Docker file for multiple architectures. In this situation, the Docker buildx tool can be used to build and deploy Docker images for numerous platforms using a single command.

This article will explain:

• What is the Purpose of Docker Buildx?
• How to Use Docker Buildx?
• Advantages of Docker Buildx in Docker

What is the Purpose of Docker Buildx?

Docker Buildx is a useful tool for creating cross-platform Docker images easily. It extends the functionality of the “docker build” command. It allows users to simultaneously build images for multiple platforms by utilizing a single command. Moreover, it can help developers reach more users and devices with their applications.

How to Use Docker Buildx?

Docker Buildx creates images for Linux, Windows, and other architectures. To use Docker Buildx, users need to create a builder instance that supports the target platforms. The builder instance is created using a “docker buildx create –name <builder-instance-name>” command or users can utilize the “docker buildx use <builder-instance-name>” command to switch to an existing one.

To build an image for multiple platforms, users need to specify the “–platform” flag with a comma-separated list of platform names. For example, to build an image for Linux amd64, Windows amd64, and Linux arm64, the following command is used:

The above-stated command creates three images with the same Docker file in the current directory and the same tag, but different architectures such as Linux x86-64 (amd64), Windows x86-64 (amd64), and Linux ARMv8 (arm64).

Advantages of Docker Buildx in Docker

Some advantages of Docker Buildx in Docker are:

• It allows you to build images for multiple platforms using a single command.
• It supports features such as caching, parallelism and output modes that can improve the efficiency and flexibility of your builds.
• It integrates with the Docker CLI and the Docker Compose file format, making it easy to use and compatible with your existing workflows.
• It leverages the Build Kit library, which is a modern and modular toolkit for building container images.

Conclusion

The Docker buildx is an experimental feature that allows users to build and deploy Docker images for numerous platforms using a single command. This can be useful for developing and deploying applications that need to run on different operating systems or architectures without having to manually create and maintain separate Docker files for each platform. Moreover, it can also be used to create images for other platforms, such as ARM or IBM Z.