Apple Container's implementation of compose functionality using familiar docker-compose YAML syntax.

Makefile

@@ -48,13 +48,22 @@ include Protobuf.Makefile
 .PHONY: all
 all: container
 all: init-block
+all: plugins
 
 .PHONY: build
 build:
 	@echo Building container binaries...
 	@$(SWIFT) --version
 	@$(SWIFT) build -c $(BUILD_CONFIGURATION) $(SWIFT_CONFIGURATION)
 
+.PHONY: plugins
+plugins: plugin-compose
+
+.PHONY: plugin-compose
+plugin-compose:
+	@echo Building container-compose plugin...
+	@cd Plugins/container-compose && $(SWIFT) build -c $(BUILD_CONFIGURATION) --product compose
+
 .PHONY: container
 # Install binaries under project directory
 container: build
@@ -87,6 +96,7 @@ $(STAGING_DIR):
 	@mkdir -p "$(join $(STAGING_DIR), libexec/container/plugins/container-runtime-linux/bin)"
 	@mkdir -p "$(join $(STAGING_DIR), libexec/container/plugins/container-network-vmnet/bin)"
 	@mkdir -p "$(join $(STAGING_DIR), libexec/container/plugins/container-core-images/bin)"
+	@mkdir -p "$(join $(STAGING_DIR), libexec/container/plugins/compose/bin)"
 
 	@install "$(BUILD_BIN_DIR)/container" "$(join $(STAGING_DIR), bin/container)"
 	@install "$(BUILD_BIN_DIR)/container-apiserver" "$(join $(STAGING_DIR), bin/container-apiserver)"
@@ -96,6 +106,10 @@ $(STAGING_DIR):
 	@install config/container-network-vmnet-config.json "$(join $(STAGING_DIR), libexec/container/plugins/container-network-vmnet/config.json)"
 	@install "$(BUILD_BIN_DIR)/container-core-images" "$(join $(STAGING_DIR), libexec/container/plugins/container-core-images/bin/container-core-images)"
 	@install config/container-core-images-config.json "$(join $(STAGING_DIR), libexec/container/plugins/container-core-images/config.json)"
+	@if [ -f "Plugins/container-compose/.build/$(BUILD_CONFIGURATION)/compose" ]; then \
+		install "Plugins/container-compose/.build/$(BUILD_CONFIGURATION)/compose" "$(join $(STAGING_DIR), libexec/container/plugins/compose/bin/compose)"; \
+		install "Plugins/container-compose/config.json" "$(join $(STAGING_DIR), libexec/container/plugins/compose/config.json)"; \
+	fi
 
 	@echo Install uninstaller script
 	@install scripts/uninstall-container.sh "$(join $(STAGING_DIR), bin/uninstall-container.sh)"
@@ -108,8 +122,10 @@ installer-pkg: $(STAGING_DIR)
 	@codesign $(CODESIGN_OPTS) --prefix=com.apple.container. "$(join $(STAGING_DIR), libexec/container/plugins/container-core-images/bin/container-core-images)"
 	@codesign $(CODESIGN_OPTS) --prefix=com.apple.container. --entitlements=signing/container-runtime-linux.entitlements "$(join $(STAGING_DIR), libexec/container/plugins/container-runtime-linux/bin/container-runtime-linux)"
 	@codesign $(CODESIGN_OPTS) --prefix=com.apple.container. --entitlements=signing/container-network-vmnet.entitlements "$(join $(STAGING_DIR), libexec/container/plugins/container-network-vmnet/bin/container-network-vmnet)"
+	@if [ -f "$(join $(STAGING_DIR), libexec/container/plugins/compose/bin/compose)" ]; then \
+		codesign $(CODESIGN_OPTS) --prefix=com.apple.container. "$(join $(STAGING_DIR), libexec/container/plugins/compose/bin/compose)"; \
+	fi
 
-	@echo Creating application installer
 	@pkgbuild --root "$(STAGING_DIR)" --identifier com.apple.container-installer --install-location /usr/local --version ${RELEASE_VERSION} $(PKG_PATH)
 	@rm -rf "$(STAGING_DIR)"
 
@@ -207,3 +223,4 @@ clean:
 	@rm -rf bin/ libexec/
 	@rm -rf _site _serve
 	@$(SWIFT) package clean
+	@cd Plugins/container-compose && $(SWIFT) package clean 2>/dev/null || true

Plugins/container-compose/BUILD.md

@@ -0,0 +1,180 @@
+# Building and Testing Container Compose Plugin
+
+## Prerequisites
+
+- macOS 15 or later
+- Swift 6.2 or later
+- Main container project dependencies
+
+## Building
+
+### From the main project root:
+
+```bash
+# Build everything including the plugin
+make all
+
+# Build only the compose plugin
+make plugin-compose
+
+# Clean build
+make clean
+```
+
+### From the plugin directory:
+
+```bash
+cd Plugins/container-compose
+
+# Build in debug mode
+swift build
+
+# Build in release mode
+swift build -c release
+
+# Run the plugin directly
+    .build/debug/compose --help
+```
+
+## Testing
+
+### Run tests from plugin directory:
+
+```bash
+cd Plugins/container-compose
+
+# Run all tests
+swift test
+
+# Run specific test
+swift test --filter ComposeParserTests
+
+# Run with verbose output
+swift test --verbose
+```
+
+### Manual testing:
+
+1. Build the plugin:
+   ```bash
+   swift build
+   ```
+
+2. Test basic functionality:
+   ```bash
+   # Validate a compose file
+    .build/debug/compose validate -f test-compose.yml
+
+   # Show help
+    .build/debug/compose --help
+    .build/debug/compose up --help
+   ```
+
+## Installation
+
+### Via main project install:
+
+```bash
+# From main project root
+make install
+```
+
+This installs the plugin to: `/usr/local/libexec/container/plugins/compose/`
+
+### Manual installation:
+
+```bash
+# Build in release mode
+cd Plugins/container-compose
+swift build -c release
+
+# Copy to plugin directory
+sudo mkdir -p /usr/local/libexec/container/plugins/compose/bin
+sudo cp .build/release/compose /usr/local/libexec/container/plugins/compose/bin/
+sudo cp config.json /usr/local/libexec/container/plugins/compose/
+```
+
+## Integration Testing
+
+After installation, test the plugin integration:
+
+```bash
+# Should work through main container CLI
+container compose --help
+container compose up --help
+
+# Create a test compose file
+cat > test-compose.yml << 'EOF'
+version: '3'
+services:
+  web:
+    image: nginx:alpine
+    ports:
+      - "8080:80"
+EOF
+
+# Test compose commands
+container compose validate -f test-compose.yml
+container compose up -d -f test-compose.yml
+container compose ps -f test-compose.yml
+container compose down -f test-compose.yml
+```
+
+## Troubleshooting
+
+### Build Errors
+
+1. **Missing dependencies**: Ensure the main container project is built first
+   ```bash
+   cd ../..
+   swift build
+   ```
+
+2. **Swift version**: Check Swift version
+   ```bash
+   swift --version
+   ```
+
+3. **Clean build**: Try a clean build
+   ```bash
+   swift package clean
+   swift build
+   ```
+
+### Runtime Errors
+
+1. **Plugin not found**: Check installation path
+   ```bash
+    ls -la /usr/local/libexec/container/plugins/compose/
+   ```
+
+2. **Permission issues**: Ensure proper permissions
+   ```bash
+    sudo chmod +x /usr/local/libexec/container/plugins/compose/bin/compose
+   ```
+
+3. **Debug output**: Enable debug logging
+   ```bash
+   container compose --debug up
+   ```
+
+## Development Workflow
+
+1. Make changes to the plugin code
+2. Build and test locally:
+   ```bash
+   swift build && swift test
+   ```
+3. Test integration:
+   ```bash
+   make -C ../.. plugin-compose
+   sudo make -C ../.. install
+   container compose --help
+   ```
+4. Submit changes via PR
+
+## Notes
+
+- The plugin uses a stub for ProgressBar to avoid dependencies on internal APIs
+- All compose functionality is self-contained in the plugin
+- The plugin can be developed and tested independently of the main project