docker doc

README.md

@@ -61,7 +61,46 @@ python jira_jotty_sync.py --direction=both
 
 ## Docker (Raspberry Pi 5 / ARM64)
 
-### Build for ARM64
+### Build for Multiple Platforms
+
+Build a multi-architecture image supporting `linux/amd64`, `linux/arm/v7`, and `linux/arm64`:
+
+```bash
+docker buildx create --use --name multi-arch-builder --driver docker-container
+docker buildx build -t "jotty-jira-sync:latest" --no-cache --platform linux/amd64,linux/arm/v7,linux/arm64 .
+```
+
+> **Note:** The `docker-container` driver stores the result in the build cache. To push to a registry, add `--push`:
+> ```bash
+> docker buildx build -t "your-registry/jotty-jira-sync:latest" --no-cache --platform linux/amd64,linux/arm/v7,linux/arm64 --push .
+> ```
+
+### Push to Registry
+
+Tag and push the image to your local registry (requires Docker insecure-registries config for HTTP):
+
+```bash
+docker tag jotty-jira-sync:latest beere5:9444/jotty-jira-sync:latest
+docker push beere5:9444/jotty-jira-sync:latest
+```
+
+If you get a `http: server gave HTTP response to HTTPS client` error, configure Docker to allow the insecure registry:
+
+```bash
+sudo mkdir -p /etc/docker
+echo '{"insecure-registries": ["beere5:9444"]}' | sudo tee /etc/docker/daemon.json
+sudo systemctl restart docker
+```
+
+### Clean Up Unused Images
+
+Remove unused Docker images to free disk space:
+
+```bash
+docker image prune -f
+```
+
+### Build for Single Platform (local)
 
 On Raspberry Pi 5 (native ARM64):
 
@@ -69,7 +108,7 @@ On Raspberry Pi 5 (native ARM64):
 docker build -t jotty-jira-sync:arm64 .
 ```
 
-From another machine using buildx:
+From another machine using buildx (single platform only):
 
 ```bash
 docker buildx build \