Dockerfile Best Practices: Multi-Stage Builds and Base Images

--- title: Building best practices linkTitle: Best practices weight: 60 description: Hints, tips and guidelines for writing clean, reliable Dockerfiles keywords: base images, dockerfile, best practices, hub, official image tags: [Best practices] aliases: - /articles/dockerfile_best-practices/ - /engine/articles/dockerfile_best-practices/ - /engine/userguide/eng-image/dockerfile_best-practices/ - /develop/develop-images/dockerfile_best-practices/ - /develop/develop-images/guidelines/ - /develop/develop-images/instructions/ - /develop/dev-best-practices/ - /develop/security-best-practices/ --- ## Use multi-stage builds Multi-stage builds let you reduce the size of your final image, by creating a cleaner separation between the building of your image and the final output. Split your Dockerfile instructions into distinct stages to make sure that the resulting output only contains the files that are needed to run the application. Using multiple stages can also let you build more efficiently by executing build steps in parallel. See [Multi-stage builds](/manuals/build/building/multi-stage.md) for more information. ### Create reusable stages If you have multiple images with a lot in common, consider creating a reusable stage that includes the shared components, and basing your unique stages on that. Docker only needs to build the common stage once. This means that your derivative images use memory on the Docker host more efficiently and load more quickly. It's also easier to maintain a common base stage ("Don't repeat yourself"), than it is to have multiple different stages doing similar things. ## Choose the right base image The first step towards achieving a secure image is to choose the right base image. When choosing an image, ensure it's built from a trusted source and keep it small. - [Docker Official Images](https://hub.docker.com/search?image_filter=official) are a curated collection that have clear documentation, promote best practices, and are regularly updated. They provide a trusted starting point for many applications. - [Verified Publisher](https://hub.docker.com/search?image_filter=store) images are high-quality images published and maintained by the organizations partnering with Docker, with Docker verifying the authenticity of the content in their repositories. - [Docker-Sponsored Open Source](https://hub.docker.com/search?image_filter=open_source) are published and maintained by open source projects sponsored by Docker through an [open source program](../../docker-hub/image-library/trusted-content.md#docker-sponsored-open-source-software-images). When you pick your base image, look out for the badges indicating that the image is part of these programs.

This section of the Dockerfile best practices guide discusses using multi-stage builds to reduce final image size and build more efficiently. It also emphasizes the importance of choosing the right base image from trusted sources like Docker Official Images, Verified Publishers, and Docker-Sponsored Open Source projects.