diff --git a/CHANGELOG.md b/CHANGELOG.md
index b3e29ef..ab096f6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,19 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.1.7] - 2026-05-10
+
+### Security
+- **APT `Clean()` now respects `DryRun`**. Previously, `apt autoclean` executed regardless of the `DryRun` option, silently defeating the safety mechanism users expect from dry-run mode. The YUM/Snap/Flatpak Clean implementations already honored DryRun; APT now matches that behavior. Regression tests added in `manager/apt/apt_clean_dryrun_test.go`.
+- **Docker test runners no longer mask test failures**. The compose entrypoints used `bash -c` with `&&` chains and trailing `|| true` on fixture-generation steps; due to bash operator precedence, the `|| true` caught failures from earlier in the chain (including `go test`), letting failed tests pass CI silently. Switched to `bash -ec` with explicit `;` separators so test failures abort immediately while fixture-generation steps remain individually allowed to fail.
+- Added `read_only: true` and `no-new-privileges:true` to the `test-all` aggregator service for defense-in-depth.
+
+### Changed
+- **`PackageInfo` JSON output now uses snake_case field names** (e.g. `package_manager`, `new_version`, `additional_data`) instead of Go's default PascalCase. Required fields (`name`, `status`, `package_manager`) are always emitted; optional fields use `omitempty`. Consumers parsing JSON output must update field names. (#40, thanks @aijanai)
+
+### Fixed
+- `go.mod` now declares `go 1.23.0` (full version) instead of `go 1.23`, resolving Go toolchain download failures in some environments. (#40)
+
 ## [0.1.6] - 2025-11-01
 
 ### Added
@@ -37,14 +50,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Technical debt cleanup and APT Upgrade method fix
 - APT Upgrade method now correctly uses `apt install` for specific packages
 
-## Recent Achievements ✅ 
+## Recent Achievements ✅
 
 ### Architecture & Code Quality
 - ✅ **CommandRunner Architecture**: Complete architectural consistency (Issue #20, PR #26)
 - ✅ **APT & YUM executeCommand Pattern**: Centralized command execution, eliminated code duplication
 - ✅ **Technical Debt Cleanup**: Fixed APT Upgrade method bug, removed misleading TODOs, verified no resource leaks
 
-### Security Enhancements  
+### Security Enhancements
 - ✅ **Security Enhancements**: Input validation for package names (Issue #23, PR #25)
 - ✅ **Command Injection Prevention**: Comprehensive ValidatePackageName implementation across all package managers
 
@@ -77,7 +90,7 @@ Current development focus areas (see [GitHub Issues](https://github.com/bluet/sy
 - **Security scanning with Snyk** - Add to CI/CD pipeline
 - **CommandRunner migration** - Complete Snap and Flatpak integration (Issues #28, #29)
 
-### Medium Priority Pending  
+### Medium Priority Pending
 - **Test coverage improvements** - YUM gaps (Issue #32), Snap & Flatpak comprehensive suites
 - **CLI improvements** - Upgrade display (Issue #3), macOS apt conflict (Issue #2)
 - **Code quality** - Context support, custom error types, DRY principle improvements
@@ -90,7 +103,7 @@ Current development focus areas (see [GitHub Issues](https://github.com/bluet/sy
 
 ### Currently Supported ✅
 - **APT** (Ubuntu/Debian) - Full feature support
-- **YUM** (Rocky Linux/AlmaLinux/RHEL) - Full feature support  
+- **YUM** (Rocky Linux/AlmaLinux/RHEL) - Full feature support
 - **Snap** (Universal packages) - Full feature support
 - **Flatpak** (Universal packages) - Full feature support
 
@@ -101,4 +114,4 @@ Current development focus areas (see [GitHub Issues](https://github.com/bluet/sy
 ### Planned 📋
 - **Homebrew** (macOS) - Planned for cross-platform expansion
 - **Chocolatey/Scoop/winget** (Windows) - Planned for Windows support
-- **Zypper** (openSUSE) - Lower priority
\ No newline at end of file
+- **Zypper** (openSUSE) - Lower priority
diff --git a/Makefile b/Makefile
index 4476ec6..01eecfe 100644
--- a/Makefile
+++ b/Makefile
@@ -88,29 +88,29 @@ install-tools:
 # Docker testing targets
 test-docker:
 	@echo "Running tests in Docker containers..."
-	docker-compose -f testing/docker/docker-compose.test.yml up --abort-on-container-exit --remove-orphans
+	docker compose -f testing/docker/docker-compose.test.yml up --abort-on-container-failure --remove-orphans
 
 test-docker-ubuntu:
 	@echo "Running Ubuntu APT tests..."
-	docker-compose -f testing/docker/docker-compose.test.yml up ubuntu-apt-test --abort-on-container-exit
+	docker compose -f testing/docker/docker-compose.test.yml up ubuntu-apt-test --abort-on-container-failure
 
 test-docker-rocky:
 	@echo "Running Rocky Linux YUM tests..."
-	docker-compose -f testing/docker/docker-compose.test.yml up rockylinux-yum-test --abort-on-container-exit
+	docker compose -f testing/docker/docker-compose.test.yml up rockylinux-yum-test --abort-on-container-failure
 
 test-docker-alma:
 	@echo "Running AlmaLinux YUM tests..."
-	docker-compose -f testing/docker/docker-compose.test.yml up almalinux-yum-test --abort-on-container-exit
+	docker compose -f testing/docker/docker-compose.test.yml up almalinux-yum-test --abort-on-container-failure
 
 # TODO: Enable when DNF support is implemented
 # test-docker-fedora:
 # 	@echo "Running Fedora DNF tests..."
-# 	docker-compose -f testing/docker/docker-compose.test.yml up fedora-dnf-test --abort-on-container-exit
+# 	docker compose -f testing/docker/docker-compose.test.yml up fedora-dnf-test --abort-on-container-failure
 
 # TODO: Enable when APK support is implemented
 # test-docker-alpine:
 # 	@echo "Running Alpine APK tests..."
-# 	docker-compose -f testing/docker/docker-compose.test.yml up alpine-apk-test --abort-on-container-exit
+# 	docker compose -f testing/docker/docker-compose.test.yml up alpine-apk-test --abort-on-container-failure
 
 test-docker-all: test-docker
 
@@ -118,13 +118,13 @@ test-docker-all: test-docker
 test-fixtures:
 	@echo "Generating test fixtures from multiple OS..."
 	@mkdir -p testing/fixtures/{apt,yum,dnf,apk}
-	docker-compose -f testing/docker/docker-compose.test.yml up --abort-on-container-exit
+	docker compose -f testing/docker/docker-compose.test.yml up --abort-on-container-failure
 	@echo "Test fixtures generated in testing/fixtures/"
 
 # Clean up Docker resources
 test-docker-clean:
 	@echo "Cleaning up Docker test resources..."
-	docker-compose -f testing/docker/docker-compose.test.yml down --volumes --remove-orphans
+	docker compose -f testing/docker/docker-compose.test.yml down --volumes --remove-orphans
 	docker system prune -f --filter "label=com.docker.compose.project=syspkg-test"
 
 # Unit tests only (no integration/system tests)
diff --git a/manager/apt/apt.go b/manager/apt/apt.go
index 18a7071..2b90e05 100644
--- a/manager/apt/apt.go
+++ b/manager/apt/apt.go
@@ -378,9 +378,6 @@ func (a *PackageManager) UpgradeAll(opts *manager.Options) ([]manager.PackageInf
 
 // Clean cleans the local package cache used by the apt package manager.
 func (a *PackageManager) Clean(opts *manager.Options) error {
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
-	defer cancel()
-
 	if opts == nil {
 		opts = &manager.Options{
 			DryRun:      false,
@@ -388,6 +385,16 @@ func (a *PackageManager) Clean(opts *manager.Options) error {
 			Verbose:     false,
 		}
 	}
+
+	// Handle dry run mode
+	if opts.DryRun {
+		log.Println("Dry run mode: would execute 'apt autoclean'")
+		return nil
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
+	defer cancel()
+
 	args := []string{"autoclean"}
 	out, err := a.executeCommand(ctx, args, opts)
 	if err != nil {
diff --git a/manager/apt/apt_clean_dryrun_test.go b/manager/apt/apt_clean_dryrun_test.go
new file mode 100644
index 0000000..7a41bac
--- /dev/null
+++ b/manager/apt/apt_clean_dryrun_test.go
@@ -0,0 +1,65 @@
+package apt_test
+
+import (
+	"testing"
+
+	"github.com/bluet/syspkg/manager"
+	"github.com/bluet/syspkg/manager/apt"
+)
+
+// TestCleanRespectsDryRun is the regression test for the security-relevant bug
+// where Clean() executed `apt autoclean` even when opts.DryRun was true.
+// Behavior contract: Clean(DryRun=true) MUST NOT execute any underlying command.
+func TestCleanRespectsDryRun(t *testing.T) {
+	mockRunner := manager.NewMockCommandRunner()
+	pm := apt.NewPackageManagerWithCustomRunner(mockRunner)
+
+	if err := pm.Clean(&manager.Options{DryRun: true}); err != nil {
+		t.Fatalf("Clean(DryRun=true) returned error: %v", err)
+	}
+
+	if got := len(mockRunner.EnvCalls); got != 0 {
+		t.Errorf("Clean(DryRun=true) executed %d non-interactive command(s); expected 0. Calls: %v",
+			got, mockRunner.EnvCalls)
+	}
+	if got := len(mockRunner.InteractiveCalls); got != 0 {
+		t.Errorf("Clean(DryRun=true) executed %d interactive command(s); expected 0. Calls: %v",
+			got, mockRunner.InteractiveCalls)
+	}
+}
+
+// TestCleanRunsWithoutDryRun guards against the Clean(DryRun) fix being
+// implemented as a blanket no-op. Without DryRun, Clean MUST invoke
+// `apt autoclean`.
+func TestCleanRunsWithoutDryRun(t *testing.T) {
+	mockRunner := manager.NewMockCommandRunner()
+	mockRunner.AddCommand("apt", []string{"autoclean"}, []byte("Reading package lists...\n"), nil)
+	pm := apt.NewPackageManagerWithCustomRunner(mockRunner)
+
+	if err := pm.Clean(&manager.Options{DryRun: false}); err != nil {
+		t.Fatalf("Clean(DryRun=false) returned error: %v", err)
+	}
+
+	if _, ok := mockRunner.EnvCalls["apt autoclean"]; !ok {
+		t.Errorf("Clean(DryRun=false) didn't invoke 'apt autoclean'. Recorded calls: %v",
+			mockRunner.EnvCalls)
+	}
+}
+
+// TestCleanRespectsDryRunWithNilOptsDefault verifies the nil-opts branch:
+// when opts == nil, the code path defaults DryRun to false, so Clean
+// SHOULD execute (proving the nil-opts default is preserved by the fix).
+func TestCleanRunsWithNilOpts(t *testing.T) {
+	mockRunner := manager.NewMockCommandRunner()
+	mockRunner.AddCommand("apt", []string{"autoclean"}, []byte("Reading package lists...\n"), nil)
+	pm := apt.NewPackageManagerWithCustomRunner(mockRunner)
+
+	if err := pm.Clean(nil); err != nil {
+		t.Fatalf("Clean(nil) returned error: %v", err)
+	}
+
+	if _, ok := mockRunner.EnvCalls["apt autoclean"]; !ok {
+		t.Errorf("Clean(nil) didn't invoke 'apt autoclean'. Recorded calls: %v",
+			mockRunner.EnvCalls)
+	}
+}
diff --git a/testing/docker/docker-compose.test.yml b/testing/docker/docker-compose.test.yml
index d1955bd..5c2ab02 100644
--- a/testing/docker/docker-compose.test.yml
+++ b/testing/docker/docker-compose.test.yml
@@ -18,13 +18,19 @@ services:
     volumes:
       - ../..:/workspace
     working_dir: /workspace
+    # NOTE: bash -ec ensures any failed required command (test, apt update)
+    # exits immediately. The `|| true` on fixture-generation lines is the
+    # explicit opt-out — those steps are allowed to fail without failing the
+    # build. Previously this used `&&` chaining which silently masked test
+    # failures because trailing `|| true` caught failures from earlier in the
+    # chain.
     command: >
-      bash -c "
-        echo 'Running Ubuntu APT tests...' &&
-        go test -v -tags='unit integration apt' ./manager/apt ./osinfo &&
-        echo 'Generating APT fixtures...' &&
-        apt update &&
-        apt search vim > testing/fixtures/apt/search-vim-ubuntu22.txt 2>/dev/null || true &&
+      bash -ec "
+        echo 'Running Ubuntu APT tests...';
+        go test -v -tags='unit integration apt' ./manager/apt ./osinfo;
+        echo 'Generating APT fixtures...';
+        apt update;
+        apt search vim > testing/fixtures/apt/search-vim-ubuntu22.txt 2>/dev/null || true;
         apt show vim > testing/fixtures/apt/show-vim-ubuntu22.txt 2>/dev/null || true
       "
 
@@ -42,13 +48,14 @@ services:
     volumes:
       - ../..:/workspace
     working_dir: /workspace
+    # See ubuntu-apt-test for rationale on bash -ec + ; separators.
     command: >
-      bash -c "
-        echo 'Running Rocky Linux YUM tests...' &&
-        go test -v -tags='unit integration yum' ./manager/yum ./osinfo &&
-        echo 'Generating YUM fixtures...' &&
-        yum search vim > testing/fixtures/yum/search-vim-rocky8.txt 2>/dev/null || true &&
-        yum info vim-enhanced > testing/fixtures/yum/info-vim-rocky8.txt 2>/dev/null || true &&
+      bash -ec "
+        echo 'Running Rocky Linux YUM tests...';
+        go test -v -tags='unit integration yum' ./manager/yum ./osinfo;
+        echo 'Generating YUM fixtures...';
+        yum search vim > testing/fixtures/yum/search-vim-rocky8.txt 2>/dev/null || true;
+        yum info vim-enhanced > testing/fixtures/yum/info-vim-rocky8.txt 2>/dev/null || true;
         yum list --installed > testing/fixtures/yum/list-installed-rocky8.txt 2>/dev/null || true
       "
 
@@ -66,12 +73,13 @@ services:
     volumes:
       - ../..:/workspace
     working_dir: /workspace
+    # See ubuntu-apt-test for rationale on bash -ec + ; separators.
     command: >
-      bash -c "
-        echo 'Running AlmaLinux YUM tests...' &&
-        go test -v -tags='unit integration yum' ./manager/yum ./osinfo &&
-        echo 'Generating YUM fixtures...' &&
-        yum search vim > testing/fixtures/yum/search-vim-alma8.txt 2>/dev/null || true &&
+      bash -ec "
+        echo 'Running AlmaLinux YUM tests...';
+        go test -v -tags='unit integration yum' ./manager/yum ./osinfo;
+        echo 'Generating YUM fixtures...';
+        yum search vim > testing/fixtures/yum/search-vim-alma8.txt 2>/dev/null || true;
         yum info vim-enhanced > testing/fixtures/yum/info-vim-alma8.txt 2>/dev/null || true
       "
 
@@ -125,14 +133,34 @@ services:
 # Test runner that runs all tests in parallel
   test-all:
     image: ubuntu:24.04
+    # Long-form depends_on with service_completed_successfully so test-all
+    # waits for the actual tests to complete before running. With short-form,
+    # test-all's `echo` could finish in milliseconds and abort the compose
+    # run (--abort-on-container-exit) before the real tests had a chance to
+    # report failure — exactly the same class of CI-honesty bug the bash -ec
+    # change in this same release fixes one layer up.
     depends_on:
-      - ubuntu-apt-test
-      - rockylinux-yum-test
-      - almalinux-yum-test
-      # - fedora-dnf-test  # TODO: Enable when DNF support is implemented
-      # - alpine-apk-test  # TODO: Enable when APK support is implemented
+      ubuntu-apt-test:
+        condition: service_completed_successfully
+      rockylinux-yum-test:
+        condition: service_completed_successfully
+      almalinux-yum-test:
+        condition: service_completed_successfully
+      # fedora-dnf-test:    # TODO: Enable when DNF support is implemented
+      #   condition: service_completed_successfully
+      # alpine-apk-test:    # TODO: Enable when APK support is implemented
+      #   condition: service_completed_successfully
+    # Defense-in-depth: this aggregator service only runs an echo, so it can
+    # safely use a read-only root, no-new-privileges, and a read-only bind
+    # mount. Required services (ubuntu/rocky/alma) need write access for
+    # fixture generation, so they don't get these constraints.
+    read_only: true
+    security_opt:
+      # Quoted to avoid YAML parser ambiguity around `key:value` parsing
+      # while preserving Docker's documented `no-new-privileges:true` form.
+      - "no-new-privileges:true"
     volumes:
-      - ../..:/workspace
+      - ../..:/workspace:ro
     working_dir: /workspace
     command: >
       bash -c "