# To build a multi-architecture Docker image

Docker's buildx tool, which is a part of Docker BuildKit. This tool allows you to create images for different platforms from a single build command. Here's a basic rundown of the steps:

1. **Enable experimental features** by setting `"experimental": "enabled"` in your Docker configuration file (`~/.docker/config.json`).

2. **Install QEMU** on your macOS to emulate different architectures:
   ```sh
   brew install qemu
   ```

3. **Create a new builder** that enables buildx and specify the platforms you want to target:
   ```sh
   docker buildx create --name mybuilder --use
   ```

4. **Inspect the builder** to ensure it's correctly configured and can build for the target platforms:
   ```sh
   docker buildx inspect mybuilder --bootstrap
   ```

5. **Build and push the image** to Docker Hub (or another registry) for the desired platforms using the `--platform` flag:
   ```sh
   docker buildx build --platform linux/amd64,linux/arm64,linux/arm/v7 -t <username>/myimage:latest --push .
   ```