diff --git a/.github/agents/copilot-instructions.md b/.github/agents/copilot-instructions.md
index c83cbd3..62ca367 100644
--- a/.github/agents/copilot-instructions.md
+++ b/.github/agents/copilot-instructions.md
@@ -30,6 +30,7 @@ ## Active Technologies
 - PostgreSQL (Sail), SQLite in tests (087-legacy-runs-removal)
 - PHP 8.4.x + Laravel 12, Filament v5, Livewire v4, Microsoft Graph integration via `GraphClientInterface` (095-graph-contracts-registry-completeness)
 - PHP 8.4.15 (Laravel 12) + Filament v5, Livewire v4, Laravel Queue, Laravel Notifications (100-alert-target-test-actions)
+- PostgreSQL (Sail locally); SQLite is used in some tests (101-golden-master-baseline-governance-v1)
 
 - PHP 8.4.15 (feat/005-bulk-operations)
 
@@ -49,7 +50,7 @@ ## Code Style
 PHP 8.4.15: Follow standard conventions
 
 ## Recent Changes
+- 101-golden-master-baseline-governance-v1: Added PHP 8.4.x
 - 100-alert-target-test-actions: Added PHP 8.4.15 (Laravel 12) + Filament v5, Livewire v4, Laravel Queue, Laravel Notifications
-- 095-graph-contracts-registry-completeness: Added PHP 8.4.x + Laravel 12, Filament v5, Livewire v4, Microsoft Graph integration via `GraphClientInterface`
 <!-- MANUAL ADDITIONS START -->
 <!-- MANUAL ADDITIONS END -->
diff --git a/app/Filament/Pages/BaselineCompareLanding.php b/app/Filament/Pages/BaselineCompareLanding.php
new file mode 100644
index 0000000..fe7055c
--- /dev/null
+++ b/app/Filament/Pages/BaselineCompareLanding.php
@@ -0,0 +1,277 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Pages;
+
+use App\Filament\Resources\FindingResource;
+use App\Models\BaselineTenantAssignment;
+use App\Models\Finding;
+use App\Models\OperationRun;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\Auth\CapabilityResolver;
+use App\Services\Baselines\BaselineCompareService;
+use App\Support\Auth\Capabilities;
+use App\Support\OperationRunLinks;
+use App\Support\OpsUx\OperationUxPresenter;
+use BackedEnum;
+use Filament\Actions\Action;
+use Filament\Notifications\Notification;
+use Filament\Pages\Page;
+use UnitEnum;
+
+class BaselineCompareLanding extends Page
+{
+    protected static string|BackedEnum|null $navigationIcon = 'heroicon-o-scale';
+
+    protected static string|UnitEnum|null $navigationGroup = 'Governance';
+
+    protected static ?string $navigationLabel = 'Soll vs Ist';
+
+    protected static ?int $navigationSort = 30;
+
+    protected string $view = 'filament.pages.baseline-compare-landing';
+
+    public ?string $state = null;
+
+    public ?string $message = null;
+
+    public ?string $profileName = null;
+
+    public ?int $profileId = null;
+
+    public ?int $snapshotId = null;
+
+    public ?int $operationRunId = null;
+
+    public ?int $findingsCount = null;
+
+    /** @var array<string, int>|null */
+    public ?array $severityCounts = null;
+
+    public static function canAccess(): bool
+    {
+        $user = auth()->user();
+
+        if (! $user instanceof User) {
+            return false;
+        }
+
+        $tenant = Tenant::current();
+
+        if (! $tenant instanceof Tenant) {
+            return false;
+        }
+
+        $resolver = app(CapabilityResolver::class);
+
+        return $resolver->can($user, $tenant, Capabilities::TENANT_VIEW);
+    }
+
+    public function mount(): void
+    {
+        $tenant = Tenant::current();
+
+        if (! $tenant instanceof Tenant) {
+            $this->state = 'no_tenant';
+            $this->message = 'No tenant selected.';
+
+            return;
+        }
+
+        $assignment = BaselineTenantAssignment::query()
+            ->where('tenant_id', $tenant->getKey())
+            ->first();
+
+        if (! $assignment instanceof BaselineTenantAssignment) {
+            $this->state = 'no_assignment';
+            $this->message = 'This tenant has no baseline assignment. A workspace manager can assign a baseline profile to this tenant.';
+
+            return;
+        }
+
+        $profile = $assignment->baselineProfile;
+
+        if ($profile === null) {
+            $this->state = 'no_assignment';
+            $this->message = 'The assigned baseline profile no longer exists.';
+
+            return;
+        }
+
+        $this->profileName = (string) $profile->name;
+        $this->profileId = (int) $profile->getKey();
+        $this->snapshotId = $profile->active_snapshot_id !== null ? (int) $profile->active_snapshot_id : null;
+
+        if ($this->snapshotId === null) {
+            $this->state = 'no_snapshot';
+            $this->message = 'The baseline profile has no active snapshot yet. A workspace manager needs to capture a snapshot first.';
+
+            return;
+        }
+
+        $latestRun = OperationRun::query()
+            ->where('tenant_id', $tenant->getKey())
+            ->where('type', 'baseline_compare')
+            ->latest('id')
+            ->first();
+
+        if ($latestRun instanceof OperationRun && in_array($latestRun->status, ['queued', 'running'], true)) {
+            $this->state = 'comparing';
+            $this->operationRunId = (int) $latestRun->getKey();
+            $this->message = 'A baseline comparison is currently in progress.';
+
+            return;
+        }
+
+        $scopeKey = 'baseline_profile:' . $profile->getKey();
+
+        $findingsQuery = Finding::query()
+            ->where('tenant_id', $tenant->getKey())
+            ->where('finding_type', Finding::FINDING_TYPE_DRIFT)
+            ->where('source', 'baseline.compare')
+            ->where('scope_key', $scopeKey);
+
+        $totalFindings = (int) (clone $findingsQuery)->count();
+
+        if ($totalFindings > 0) {
+            $this->state = 'ready';
+            $this->findingsCount = $totalFindings;
+            $this->severityCounts = [
+                'high' => (int) (clone $findingsQuery)->where('severity', Finding::SEVERITY_HIGH)->count(),
+                'medium' => (int) (clone $findingsQuery)->where('severity', Finding::SEVERITY_MEDIUM)->count(),
+                'low' => (int) (clone $findingsQuery)->where('severity', Finding::SEVERITY_LOW)->count(),
+            ];
+
+            if ($latestRun instanceof OperationRun) {
+                $this->operationRunId = (int) $latestRun->getKey();
+            }
+
+            return;
+        }
+
+        if ($latestRun instanceof OperationRun && $latestRun->status === 'completed' && $latestRun->outcome === 'succeeded') {
+            $this->state = 'ready';
+            $this->findingsCount = 0;
+            $this->operationRunId = (int) $latestRun->getKey();
+            $this->message = 'No drift findings for this baseline comparison. The tenant matches the baseline.';
+
+            return;
+        }
+
+        $this->state = 'idle';
+        $this->message = 'Baseline profile is assigned and has a snapshot. Run "Compare Now" to check for drift.';
+    }
+
+    /**
+     * @return array<Action>
+     */
+    protected function getHeaderActions(): array
+    {
+        return [
+            $this->compareNowAction(),
+        ];
+    }
+
+    private function compareNowAction(): Action
+    {
+        return Action::make('compareNow')
+            ->label('Compare Now')
+            ->icon('heroicon-o-play')
+            ->requiresConfirmation()
+            ->modalHeading('Start baseline comparison')
+            ->modalDescription('This will compare the current tenant inventory against the assigned baseline snapshot and generate drift findings.')
+            ->visible(fn (): bool => $this->canCompare())
+            ->disabled(fn (): bool => ! in_array($this->state, ['idle', 'ready'], true))
+            ->action(function (): void {
+                $user = auth()->user();
+
+                if (! $user instanceof User) {
+                    Notification::make()->title('Not authenticated')->danger()->send();
+
+                    return;
+                }
+
+                $tenant = Tenant::current();
+
+                if (! $tenant instanceof Tenant) {
+                    Notification::make()->title('No tenant context')->danger()->send();
+
+                    return;
+                }
+
+                $service = app(BaselineCompareService::class);
+                $result = $service->startCompare($tenant, $user);
+
+                if (! ($result['ok'] ?? false)) {
+                    Notification::make()
+                        ->title('Cannot start comparison')
+                        ->body('Reason: ' . ($result['reason_code'] ?? 'unknown'))
+                        ->danger()
+                        ->send();
+
+                    return;
+                }
+
+                $run = $result['run'] ?? null;
+
+                if ($run instanceof OperationRun) {
+                    $this->operationRunId = (int) $run->getKey();
+                }
+
+                $this->state = 'comparing';
+
+                Notification::make()
+                    ->title('Baseline comparison started')
+                    ->body('A background job will compute drift against the baseline snapshot.')
+                    ->success()
+                    ->send();
+            });
+    }
+
+    private function canCompare(): bool
+    {
+        $user = auth()->user();
+
+        if (! $user instanceof User) {
+            return false;
+        }
+
+        $tenant = Tenant::current();
+
+        if (! $tenant instanceof Tenant) {
+            return false;
+        }
+
+        $resolver = app(CapabilityResolver::class);
+
+        return $resolver->can($user, $tenant, Capabilities::TENANT_SYNC);
+    }
+
+    public function getFindingsUrl(): ?string
+    {
+        $tenant = Tenant::current();
+
+        if (! $tenant instanceof Tenant) {
+            return null;
+        }
+
+        return FindingResource::getUrl('index', tenant: $tenant);
+    }
+
+    public function getRunUrl(): ?string
+    {
+        if ($this->operationRunId === null) {
+            return null;
+        }
+
+        $tenant = Tenant::current();
+
+        if (! $tenant instanceof Tenant) {
+            return null;
+        }
+
+        return OperationRunLinks::view($this->operationRunId, $tenant);
+    }
+}
diff --git a/app/Filament/Pages/TenantDashboard.php b/app/Filament/Pages/TenantDashboard.php
index defca63..bacefac 100644
--- a/app/Filament/Pages/TenantDashboard.php
+++ b/app/Filament/Pages/TenantDashboard.php
@@ -4,6 +4,7 @@
 
 namespace App\Filament\Pages;
 
+use App\Filament\Widgets\Dashboard\BaselineCompareNow;
 use App\Filament\Widgets\Dashboard\DashboardKpis;
 use App\Filament\Widgets\Dashboard\NeedsAttention;
 use App\Filament\Widgets\Dashboard\RecentDriftFindings;
@@ -31,6 +32,7 @@ public function getWidgets(): array
         return [
             DashboardKpis::class,
             NeedsAttention::class,
+            BaselineCompareNow::class,
             RecentDriftFindings::class,
             RecentOperations::class,
         ];
diff --git a/app/Filament/Resources/BaselineProfileResource.php b/app/Filament/Resources/BaselineProfileResource.php
new file mode 100644
index 0000000..23ad4b1
--- /dev/null
+++ b/app/Filament/Resources/BaselineProfileResource.php
@@ -0,0 +1,341 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources;
+
+use App\Filament\Resources\BaselineProfileResource\Pages;
+use App\Models\BaselineProfile;
+use App\Models\User;
+use App\Models\Workspace;
+use App\Services\Audit\WorkspaceAuditLogger;
+use App\Support\Audit\AuditActionId;
+use App\Support\Auth\Capabilities;
+use App\Support\Badges\BadgeDomain;
+use App\Support\Badges\BadgeRenderer;
+use App\Support\Inventory\InventoryPolicyTypeMeta;
+use App\Support\Rbac\WorkspaceUiEnforcement;
+use App\Support\Ui\ActionSurface\ActionSurfaceDeclaration;
+use App\Support\Ui\ActionSurface\Enums\ActionSurfaceInspectAffordance;
+use App\Support\Ui\ActionSurface\Enums\ActionSurfaceProfile;
+use App\Support\Ui\ActionSurface\Enums\ActionSurfaceSlot;
+use App\Support\Workspaces\WorkspaceContext;
+use BackedEnum;
+use Filament\Actions\Action;
+use Filament\Actions\ActionGroup;
+use Filament\Actions\BulkActionGroup;
+use Filament\Facades\Filament;
+use Filament\Forms\Components\Select;
+use Filament\Forms\Components\Textarea;
+use Filament\Forms\Components\TextInput;
+use Filament\Notifications\Notification;
+use Filament\Resources\Resource;
+use Filament\Schemas\Schema;
+use Filament\Tables\Columns\TextColumn;
+use Filament\Tables\Table;
+use Illuminate\Auth\Access\AuthorizationException;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Model;
+use UnitEnum;
+
+class BaselineProfileResource extends Resource
+{
+    protected static bool $isScopedToTenant = false;
+
+    protected static ?string $model = BaselineProfile::class;
+
+    protected static ?string $slug = 'baseline-profiles';
+
+    protected static bool $isGloballySearchable = false;
+
+    protected static ?string $recordTitleAttribute = 'name';
+
+    protected static string|BackedEnum|null $navigationIcon = 'heroicon-o-shield-check';
+
+    protected static string|UnitEnum|null $navigationGroup = 'Governance';
+
+    protected static ?string $navigationLabel = 'Baselines';
+
+    protected static ?int $navigationSort = 1;
+
+    public static function shouldRegisterNavigation(): bool
+    {
+        if (Filament::getCurrentPanel()?->getId() !== 'admin') {
+            return false;
+        }
+
+        return parent::shouldRegisterNavigation();
+    }
+
+    public static function canViewAny(): bool
+    {
+        $user = auth()->user();
+
+        if (! $user instanceof User) {
+            return false;
+        }
+
+        $workspace = self::resolveWorkspace();
+
+        if (! $workspace instanceof Workspace) {
+            return false;
+        }
+
+        $resolver = app(\App\Services\Auth\WorkspaceCapabilityResolver::class);
+
+        return $resolver->isMember($user, $workspace)
+            && $resolver->can($user, $workspace, Capabilities::WORKSPACE_BASELINES_VIEW);
+    }
+
+    public static function canCreate(): bool
+    {
+        return self::hasManageCapability();
+    }
+
+    public static function canEdit(Model $record): bool
+    {
+        return self::hasManageCapability();
+    }
+
+    public static function canDelete(Model $record): bool
+    {
+        return self::hasManageCapability();
+    }
+
+    public static function canView(Model $record): bool
+    {
+        return self::canViewAny();
+    }
+
+    public static function actionSurfaceDeclaration(): ActionSurfaceDeclaration
+    {
+        return ActionSurfaceDeclaration::forResource(ActionSurfaceProfile::CrudListAndView)
+            ->satisfy(ActionSurfaceSlot::ListHeader, 'Header action: Create baseline profile (capability-gated).')
+            ->satisfy(ActionSurfaceSlot::InspectAffordance, ActionSurfaceInspectAffordance::ViewAction->value)
+            ->satisfy(ActionSurfaceSlot::ListRowMoreMenu, 'Secondary row actions (edit, archive) under "More".')
+            ->exempt(ActionSurfaceSlot::ListBulkMoreGroup, 'No bulk mutations for baseline profiles in v1.')
+            ->satisfy(ActionSurfaceSlot::ListEmptyState, 'List defines empty-state create CTA.')
+            ->satisfy(ActionSurfaceSlot::DetailHeader, 'View page provides capture + edit actions.');
+    }
+
+    public static function getEloquentQuery(): Builder
+    {
+        $workspaceId = app(WorkspaceContext::class)->currentWorkspaceId(request());
+
+        return parent::getEloquentQuery()
+            ->with(['activeSnapshot', 'createdByUser'])
+            ->when(
+                $workspaceId !== null,
+                fn (Builder $query): Builder => $query->where('workspace_id', (int) $workspaceId),
+            )
+            ->when(
+                $workspaceId === null,
+                fn (Builder $query): Builder => $query->whereRaw('1 = 0'),
+            );
+    }
+
+    public static function form(Schema $schema): Schema
+    {
+        return $schema
+            ->schema([
+                TextInput::make('name')
+                    ->required()
+                    ->maxLength(255),
+                Textarea::make('description')
+                    ->rows(3)
+                    ->maxLength(1000),
+                TextInput::make('version_label')
+                    ->label('Version label')
+                    ->maxLength(50),
+                Select::make('status')
+                    ->required()
+                    ->options([
+                        BaselineProfile::STATUS_DRAFT => 'Draft',
+                        BaselineProfile::STATUS_ACTIVE => 'Active',
+                        BaselineProfile::STATUS_ARCHIVED => 'Archived',
+                    ])
+                    ->default(BaselineProfile::STATUS_DRAFT)
+                    ->native(false),
+                Select::make('scope_jsonb.policy_types')
+                    ->label('Policy type scope')
+                    ->multiple()
+                    ->options(self::policyTypeOptions())
+                    ->helperText('Leave empty to include all policy types.')
+                    ->native(false),
+            ]);
+    }
+
+    public static function table(Table $table): Table
+    {
+        $workspace = self::resolveWorkspace();
+
+        return $table
+            ->defaultSort('name')
+            ->columns([
+                TextColumn::make('name')
+                    ->searchable()
+                    ->sortable(),
+                TextColumn::make('status')
+                    ->badge()
+                    ->formatStateUsing(BadgeRenderer::label(BadgeDomain::BaselineProfileStatus))
+                    ->color(BadgeRenderer::color(BadgeDomain::BaselineProfileStatus))
+                    ->icon(BadgeRenderer::icon(BadgeDomain::BaselineProfileStatus))
+                    ->sortable(),
+                TextColumn::make('version_label')
+                    ->label('Version')
+                    ->placeholder('—'),
+                TextColumn::make('activeSnapshot.captured_at')
+                    ->label('Last snapshot')
+                    ->dateTime()
+                    ->placeholder('No snapshot'),
+                TextColumn::make('created_at')
+                    ->dateTime()
+                    ->sortable()
+                    ->toggleable(isToggledHiddenByDefault: true),
+            ])
+            ->actions([
+                Action::make('view')
+                    ->label('View')
+                    ->url(fn (BaselineProfile $record): string => static::getUrl('view', ['record' => $record]))
+                    ->icon('heroicon-o-eye'),
+                ActionGroup::make([
+                    Action::make('edit')
+                        ->label('Edit')
+                        ->url(fn (BaselineProfile $record): string => static::getUrl('edit', ['record' => $record]))
+                        ->icon('heroicon-o-pencil-square')
+                        ->visible(fn (): bool => self::hasManageCapability()),
+                    self::archiveTableAction($workspace),
+                ])->label('More'),
+            ])
+            ->bulkActions([
+                BulkActionGroup::make([])->label('More'),
+            ])
+            ->emptyStateHeading('No baseline profiles')
+            ->emptyStateDescription('Create a baseline profile to define what "good" looks like for your tenants.')
+            ->emptyStateActions([
+                Action::make('create')
+                    ->label('Create baseline profile')
+                    ->url(fn (): string => static::getUrl('create'))
+                    ->icon('heroicon-o-plus')
+                    ->visible(fn (): bool => self::hasManageCapability()),
+            ]);
+    }
+
+    public static function getRelations(): array
+    {
+        return [
+            BaselineProfileResource\RelationManagers\BaselineTenantAssignmentsRelationManager::class,
+        ];
+    }
+
+    public static function getPages(): array
+    {
+        return [
+            'index' => Pages\ListBaselineProfiles::route('/'),
+            'create' => Pages\CreateBaselineProfile::route('/create'),
+            'view' => Pages\ViewBaselineProfile::route('/{record}'),
+            'edit' => Pages\EditBaselineProfile::route('/{record}/edit'),
+        ];
+    }
+
+    /**
+     * @return array<string, string>
+     */
+    public static function policyTypeOptions(): array
+    {
+        return collect(InventoryPolicyTypeMeta::all())
+            ->filter(fn (array $row): bool => filled($row['type'] ?? null))
+            ->mapWithKeys(fn (array $row): array => [
+                (string) $row['type'] => (string) ($row['label'] ?? $row['type']),
+            ])
+            ->sort()
+            ->all();
+    }
+
+    /**
+     * @param  array<string, mixed>  $metadata
+     */
+    public static function audit(BaselineProfile $record, AuditActionId $actionId, array $metadata): void
+    {
+        $workspace = $record->workspace;
+
+        if ($workspace === null) {
+            return;
+        }
+
+        $actor = auth()->user();
+
+        app(WorkspaceAuditLogger::class)->log(
+            workspace: $workspace,
+            action: $actionId->value,
+            context: ['metadata' => $metadata],
+            actor: $actor instanceof User ? $actor : null,
+            resourceType: 'baseline_profile',
+            resourceId: (string) $record->getKey(),
+        );
+    }
+
+    private static function resolveWorkspace(): ?Workspace
+    {
+        $workspaceId = app(WorkspaceContext::class)->currentWorkspaceId(request());
+
+        if ($workspaceId === null) {
+            return null;
+        }
+
+        return Workspace::query()->whereKey($workspaceId)->first();
+    }
+
+    private static function hasManageCapability(): bool
+    {
+        $user = auth()->user();
+        $workspace = self::resolveWorkspace();
+
+        if (! $user instanceof User || ! $workspace instanceof Workspace) {
+            return false;
+        }
+
+        $resolver = app(\App\Services\Auth\WorkspaceCapabilityResolver::class);
+
+        return $resolver->isMember($user, $workspace)
+            && $resolver->can($user, $workspace, Capabilities::WORKSPACE_BASELINES_MANAGE);
+    }
+
+    private static function archiveTableAction(?Workspace $workspace): Action
+    {
+        $action = Action::make('archive')
+            ->label('Archive')
+            ->icon('heroicon-o-archive-box')
+            ->color('warning')
+            ->requiresConfirmation()
+            ->modalHeading('Archive baseline profile')
+            ->modalDescription('Archiving is permanent in v1. This profile can no longer be used for captures or compares.')
+            ->visible(fn (BaselineProfile $record): bool => $record->status !== BaselineProfile::STATUS_ARCHIVED && self::hasManageCapability())
+            ->action(function (BaselineProfile $record): void {
+                if (! self::hasManageCapability()) {
+                    throw new AuthorizationException;
+                }
+
+                $record->forceFill(['status' => BaselineProfile::STATUS_ARCHIVED])->save();
+
+                self::audit($record, AuditActionId::BaselineProfileArchived, [
+                    'baseline_profile_id' => (int) $record->getKey(),
+                    'name' => (string) $record->name,
+                ]);
+
+                Notification::make()
+                    ->title('Baseline profile archived')
+                    ->success()
+                    ->send();
+            });
+
+        if ($workspace instanceof Workspace) {
+            $action = WorkspaceUiEnforcement::forTableAction($action, $workspace)
+                ->requireCapability(Capabilities::WORKSPACE_BASELINES_MANAGE)
+                ->destructive()
+                ->apply();
+        }
+
+        return $action;
+    }
+}
diff --git a/app/Filament/Resources/BaselineProfileResource/Pages/CreateBaselineProfile.php b/app/Filament/Resources/BaselineProfileResource/Pages/CreateBaselineProfile.php
new file mode 100644
index 0000000..475259b
--- /dev/null
+++ b/app/Filament/Resources/BaselineProfileResource/Pages/CreateBaselineProfile.php
@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources\BaselineProfileResource\Pages;
+
+use App\Filament\Resources\BaselineProfileResource;
+use App\Models\BaselineProfile;
+use App\Models\User;
+use App\Support\Audit\AuditActionId;
+use App\Support\Workspaces\WorkspaceContext;
+use Filament\Notifications\Notification;
+use Filament\Resources\Pages\CreateRecord;
+
+class CreateBaselineProfile extends CreateRecord
+{
+    protected static string $resource = BaselineProfileResource::class;
+
+    /**
+     * @param  array<string, mixed>  $data
+     * @return array<string, mixed>
+     */
+    protected function mutateFormDataBeforeCreate(array $data): array
+    {
+        $workspaceId = app(WorkspaceContext::class)->currentWorkspaceId(request());
+        $data['workspace_id'] = (int) $workspaceId;
+
+        $user = auth()->user();
+        $data['created_by_user_id'] = $user instanceof User ? $user->getKey() : null;
+
+        $policyTypes = $data['scope_jsonb']['policy_types'] ?? [];
+        $data['scope_jsonb'] = ['policy_types' => is_array($policyTypes) ? array_values($policyTypes) : []];
+
+        return $data;
+    }
+
+    protected function afterCreate(): void
+    {
+        $record = $this->record;
+
+        if (! $record instanceof BaselineProfile) {
+            return;
+        }
+
+        BaselineProfileResource::audit($record, AuditActionId::BaselineProfileCreated, [
+            'baseline_profile_id' => (int) $record->getKey(),
+            'name' => (string) $record->name,
+            'status' => (string) $record->status,
+        ]);
+
+        Notification::make()
+            ->title('Baseline profile created')
+            ->success()
+            ->send();
+    }
+}
diff --git a/app/Filament/Resources/BaselineProfileResource/Pages/EditBaselineProfile.php b/app/Filament/Resources/BaselineProfileResource/Pages/EditBaselineProfile.php
new file mode 100644
index 0000000..49284ec
--- /dev/null
+++ b/app/Filament/Resources/BaselineProfileResource/Pages/EditBaselineProfile.php
@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources\BaselineProfileResource\Pages;
+
+use App\Filament\Resources\BaselineProfileResource;
+use App\Models\BaselineProfile;
+use App\Support\Audit\AuditActionId;
+use Filament\Notifications\Notification;
+use Filament\Resources\Pages\EditRecord;
+
+class EditBaselineProfile extends EditRecord
+{
+    protected static string $resource = BaselineProfileResource::class;
+
+    /**
+     * @param  array<string, mixed>  $data
+     * @return array<string, mixed>
+     */
+    protected function mutateFormDataBeforeSave(array $data): array
+    {
+        $policyTypes = $data['scope_jsonb']['policy_types'] ?? [];
+        $data['scope_jsonb'] = ['policy_types' => is_array($policyTypes) ? array_values($policyTypes) : []];
+
+        return $data;
+    }
+
+    protected function afterSave(): void
+    {
+        $record = $this->record;
+
+        if (! $record instanceof BaselineProfile) {
+            return;
+        }
+
+        BaselineProfileResource::audit($record, AuditActionId::BaselineProfileUpdated, [
+            'baseline_profile_id' => (int) $record->getKey(),
+            'name' => (string) $record->name,
+            'status' => (string) $record->status,
+        ]);
+
+        Notification::make()
+            ->title('Baseline profile updated')
+            ->success()
+            ->send();
+    }
+}
diff --git a/app/Filament/Resources/BaselineProfileResource/Pages/ListBaselineProfiles.php b/app/Filament/Resources/BaselineProfileResource/Pages/ListBaselineProfiles.php
new file mode 100644
index 0000000..7abf445
--- /dev/null
+++ b/app/Filament/Resources/BaselineProfileResource/Pages/ListBaselineProfiles.php
@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources\BaselineProfileResource\Pages;
+
+use App\Filament\Resources\BaselineProfileResource;
+use Filament\Actions\CreateAction;
+use Filament\Resources\Pages\ListRecords;
+
+class ListBaselineProfiles extends ListRecords
+{
+    protected static string $resource = BaselineProfileResource::class;
+
+    protected function getHeaderActions(): array
+    {
+        return [
+            CreateAction::make()
+                ->label('Create baseline profile')
+                ->disabled(fn (): bool => ! BaselineProfileResource::canCreate()),
+        ];
+    }
+}
diff --git a/app/Filament/Resources/BaselineProfileResource/Pages/ViewBaselineProfile.php b/app/Filament/Resources/BaselineProfileResource/Pages/ViewBaselineProfile.php
new file mode 100644
index 0000000..c4e8989
--- /dev/null
+++ b/app/Filament/Resources/BaselineProfileResource/Pages/ViewBaselineProfile.php
@@ -0,0 +1,142 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources\BaselineProfileResource\Pages;
+
+use App\Filament\Resources\BaselineProfileResource;
+use App\Models\BaselineProfile;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Models\Workspace;
+use App\Services\Baselines\BaselineCaptureService;
+use App\Support\Auth\Capabilities;
+use App\Support\Workspaces\WorkspaceContext;
+use Filament\Actions\Action;
+use Filament\Actions\EditAction;
+use Filament\Forms\Components\Select;
+use Filament\Notifications\Notification;
+use Filament\Resources\Pages\ViewRecord;
+
+class ViewBaselineProfile extends ViewRecord
+{
+    protected static string $resource = BaselineProfileResource::class;
+
+    protected function getHeaderActions(): array
+    {
+        return [
+            $this->captureAction(),
+            EditAction::make()
+                ->visible(fn (): bool => $this->hasManageCapability()),
+        ];
+    }
+
+    private function captureAction(): Action
+    {
+        return Action::make('capture')
+            ->label('Capture Snapshot')
+            ->icon('heroicon-o-camera')
+            ->color('primary')
+            ->visible(fn (): bool => $this->hasManageCapability())
+            ->disabled(fn (): bool => ! $this->hasManageCapability())
+            ->tooltip(fn (): ?string => ! $this->hasManageCapability() ? 'You need manage permission to capture snapshots.' : null)
+            ->requiresConfirmation()
+            ->modalHeading('Capture Baseline Snapshot')
+            ->modalDescription('Select the source tenant whose current inventory will be captured as the baseline snapshot.')
+            ->form([
+                Select::make('source_tenant_id')
+                    ->label('Source Tenant')
+                    ->options(fn (): array => $this->getWorkspaceTenantOptions())
+                    ->required()
+                    ->searchable(),
+            ])
+            ->action(function (array $data): void {
+                $user = auth()->user();
+
+                if (! $user instanceof User || ! $this->hasManageCapability()) {
+                    Notification::make()
+                        ->title('Permission denied')
+                        ->danger()
+                        ->send();
+
+                    return;
+                }
+
+                /** @var BaselineProfile $profile */
+                $profile = $this->getRecord();
+                $sourceTenant = Tenant::query()->find((int) $data['source_tenant_id']);
+
+                if (! $sourceTenant instanceof Tenant) {
+                    Notification::make()
+                        ->title('Source tenant not found')
+                        ->danger()
+                        ->send();
+
+                    return;
+                }
+
+                $service = app(BaselineCaptureService::class);
+                $result = $service->startCapture($profile, $sourceTenant, $user);
+
+                if (! $result['ok']) {
+                    Notification::make()
+                        ->title('Cannot start capture')
+                        ->body('Reason: ' . str_replace('.', ' ', (string) ($result['reason_code'] ?? 'unknown')))
+                        ->danger()
+                        ->send();
+
+                    return;
+                }
+
+                Notification::make()
+                    ->title('Capture enqueued')
+                    ->body('Baseline snapshot capture has been started.')
+                    ->success()
+                    ->send();
+            });
+    }
+
+    /**
+     * @return array<int, string>
+     */
+    private function getWorkspaceTenantOptions(): array
+    {
+        $workspaceId = app(WorkspaceContext::class)->currentWorkspaceId(request());
+
+        if ($workspaceId === null) {
+            return [];
+        }
+
+        return Tenant::query()
+            ->where('workspace_id', $workspaceId)
+            ->orderBy('display_name')
+            ->pluck('display_name', 'id')
+            ->all();
+    }
+
+    private function hasManageCapability(): bool
+    {
+        $user = auth()->user();
+
+        if (! $user instanceof User) {
+            return false;
+        }
+
+        $workspaceId = app(WorkspaceContext::class)->currentWorkspaceId(request());
+
+        if ($workspaceId === null) {
+            return false;
+        }
+
+        $workspace = Workspace::query()->whereKey($workspaceId)->first();
+
+        if (! $workspace instanceof Workspace) {
+            return false;
+        }
+
+        $resolver = app(\App\Services\Auth\WorkspaceCapabilityResolver::class);
+
+        return $resolver->isMember($user, $workspace)
+            && $resolver->can($user, $workspace, Capabilities::WORKSPACE_BASELINES_MANAGE);
+    }
+}
diff --git a/app/Filament/Resources/BaselineProfileResource/RelationManagers/BaselineTenantAssignmentsRelationManager.php b/app/Filament/Resources/BaselineProfileResource/RelationManagers/BaselineTenantAssignmentsRelationManager.php
new file mode 100644
index 0000000..2342391
--- /dev/null
+++ b/app/Filament/Resources/BaselineProfileResource/RelationManagers/BaselineTenantAssignmentsRelationManager.php
@@ -0,0 +1,246 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources\BaselineProfileResource\RelationManagers;
+
+use App\Models\BaselineProfile;
+use App\Models\BaselineTenantAssignment;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Models\Workspace;
+use App\Services\Audit\WorkspaceAuditLogger;
+use App\Support\Auth\Capabilities;
+use App\Support\Ui\ActionSurface\ActionSurfaceDeclaration;
+use App\Support\Ui\ActionSurface\Enums\ActionSurfaceInspectAffordance;
+use App\Support\Ui\ActionSurface\Enums\ActionSurfaceProfile;
+use App\Support\Ui\ActionSurface\Enums\ActionSurfaceSlot;
+use App\Support\Workspaces\WorkspaceContext;
+use Filament\Actions\Action;
+use Filament\Forms\Components\Select;
+use Filament\Notifications\Notification;
+use Filament\Resources\RelationManagers\RelationManager;
+use Filament\Tables;
+use Filament\Tables\Table;
+
+class BaselineTenantAssignmentsRelationManager extends RelationManager
+{
+    protected static string $relationship = 'tenantAssignments';
+
+    protected static ?string $title = 'Tenant assignments';
+
+    public static function actionSurfaceDeclaration(): ActionSurfaceDeclaration
+    {
+        return ActionSurfaceDeclaration::forRelationManager(ActionSurfaceProfile::RelationManager)
+            ->satisfy(ActionSurfaceSlot::ListHeader, 'Header action: Assign tenant (manage-gated).')
+            ->satisfy(ActionSurfaceSlot::InspectAffordance, ActionSurfaceInspectAffordance::ClickableRow->value)
+            ->exempt(ActionSurfaceSlot::ListRowMoreMenu, 'v1 assignments have no row-level actions beyond delete.')
+            ->exempt(ActionSurfaceSlot::ListBulkMoreGroup, 'No bulk mutations for assignments in v1.')
+            ->satisfy(ActionSurfaceSlot::ListEmptyState, 'Empty state encourages assigning a tenant.');
+    }
+
+    public function table(Table $table): Table
+    {
+        return $table
+            ->columns([
+                Tables\Columns\TextColumn::make('tenant.display_name')
+                    ->label('Tenant')
+                    ->searchable(),
+                Tables\Columns\TextColumn::make('assignedByUser.name')
+                    ->label('Assigned by')
+                    ->placeholder('—'),
+                Tables\Columns\TextColumn::make('created_at')
+                    ->label('Assigned at')
+                    ->dateTime()
+                    ->sortable(),
+            ])
+            ->headerActions([
+                $this->assignTenantAction(),
+            ])
+            ->actions([
+                $this->removeAssignmentAction(),
+            ])
+            ->emptyStateHeading('No tenants assigned')
+            ->emptyStateDescription('Assign a tenant to compare its state against this baseline profile.')
+            ->emptyStateActions([
+                $this->assignTenantAction(),
+            ]);
+    }
+
+    private function assignTenantAction(): Action
+    {
+        return Action::make('assign')
+            ->label('Assign Tenant')
+            ->icon('heroicon-o-plus')
+            ->visible(fn (): bool => $this->hasManageCapability())
+            ->form([
+                Select::make('tenant_id')
+                    ->label('Tenant')
+                    ->options(fn (): array => $this->getAvailableTenantOptions())
+                    ->required()
+                    ->searchable(),
+            ])
+            ->action(function (array $data): void {
+                $user = auth()->user();
+
+                if (! $user instanceof User || ! $this->hasManageCapability()) {
+                    Notification::make()
+                        ->title('Permission denied')
+                        ->danger()
+                        ->send();
+
+                    return;
+                }
+
+                /** @var BaselineProfile $profile */
+                $profile = $this->getOwnerRecord();
+                $tenantId = (int) $data['tenant_id'];
+
+                $existing = BaselineTenantAssignment::query()
+                    ->where('workspace_id', $profile->workspace_id)
+                    ->where('tenant_id', $tenantId)
+                    ->first();
+
+                if ($existing instanceof BaselineTenantAssignment) {
+                    Notification::make()
+                        ->title('Tenant already assigned')
+                        ->body('This tenant already has a baseline assignment in this workspace.')
+                        ->warning()
+                        ->send();
+
+                    return;
+                }
+
+                $assignment = BaselineTenantAssignment::create([
+                    'workspace_id' => (int) $profile->workspace_id,
+                    'tenant_id' => $tenantId,
+                    'baseline_profile_id' => (int) $profile->getKey(),
+                    'assigned_by_user_id' => (int) $user->getKey(),
+                ]);
+
+                $this->auditAssignment($profile, $assignment, $user, 'created');
+
+                Notification::make()
+                    ->title('Tenant assigned')
+                    ->success()
+                    ->send();
+            });
+    }
+
+    private function removeAssignmentAction(): Action
+    {
+        return Action::make('remove')
+            ->label('Remove')
+            ->icon('heroicon-o-trash')
+            ->color('danger')
+            ->visible(fn (): bool => $this->hasManageCapability())
+            ->requiresConfirmation()
+            ->modalHeading('Remove tenant assignment')
+            ->modalDescription('Are you sure you want to remove this tenant assignment? This will not delete any existing findings.')
+            ->action(function (BaselineTenantAssignment $record): void {
+                $user = auth()->user();
+
+                if (! $user instanceof User || ! $this->hasManageCapability()) {
+                    Notification::make()
+                        ->title('Permission denied')
+                        ->danger()
+                        ->send();
+
+                    return;
+                }
+
+                /** @var BaselineProfile $profile */
+                $profile = $this->getOwnerRecord();
+
+                $this->auditAssignment($profile, $record, $user, 'removed');
+
+                $record->delete();
+
+                Notification::make()
+                    ->title('Assignment removed')
+                    ->success()
+                    ->send();
+            });
+    }
+
+    /**
+     * @return array<int, string>
+     */
+    private function getAvailableTenantOptions(): array
+    {
+        /** @var BaselineProfile $profile */
+        $profile = $this->getOwnerRecord();
+
+        $assignedTenantIds = BaselineTenantAssignment::query()
+            ->where('workspace_id', $profile->workspace_id)
+            ->pluck('tenant_id')
+            ->all();
+
+        $query = Tenant::query()
+            ->where('workspace_id', $profile->workspace_id)
+            ->orderBy('display_name');
+
+        if (! empty($assignedTenantIds)) {
+            $query->whereNotIn('id', $assignedTenantIds);
+        }
+
+        return $query->pluck('display_name', 'id')->all();
+    }
+
+    private function auditAssignment(
+        BaselineProfile $profile,
+        BaselineTenantAssignment $assignment,
+        User $user,
+        string $action,
+    ): void {
+        $workspace = Workspace::query()->find($profile->workspace_id);
+
+        if (! $workspace instanceof Workspace) {
+            return;
+        }
+
+        $tenant = Tenant::query()->find($assignment->tenant_id);
+
+        $auditLogger = app(WorkspaceAuditLogger::class);
+
+        $auditLogger->log(
+            workspace: $workspace,
+            action: 'baseline.assignment.' . $action,
+            context: [
+                'baseline_profile_id' => (int) $profile->getKey(),
+                'baseline_profile_name' => (string) $profile->name,
+                'tenant_id' => (int) $assignment->tenant_id,
+                'tenant_name' => $tenant instanceof Tenant ? (string) $tenant->display_name : '—',
+            ],
+            actor: $user,
+            resourceType: 'baseline_profile',
+            resourceId: (string) $profile->getKey(),
+        );
+    }
+
+    private function hasManageCapability(): bool
+    {
+        $user = auth()->user();
+
+        if (! $user instanceof User) {
+            return false;
+        }
+
+        $workspaceId = app(WorkspaceContext::class)->currentWorkspaceId(request());
+
+        if ($workspaceId === null) {
+            return false;
+        }
+
+        $workspace = Workspace::query()->whereKey($workspaceId)->first();
+
+        if (! $workspace instanceof Workspace) {
+            return false;
+        }
+
+        $resolver = app(\App\Services\Auth\WorkspaceCapabilityResolver::class);
+
+        return $resolver->isMember($user, $workspace)
+            && $resolver->can($user, $workspace, Capabilities::WORKSPACE_BASELINES_MANAGE);
+    }
+}
diff --git a/app/Filament/Widgets/Dashboard/BaselineCompareNow.php b/app/Filament/Widgets/Dashboard/BaselineCompareNow.php
new file mode 100644
index 0000000..e2113a3
--- /dev/null
+++ b/app/Filament/Widgets/Dashboard/BaselineCompareNow.php
@@ -0,0 +1,74 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Widgets\Dashboard;
+
+use App\Models\BaselineTenantAssignment;
+use App\Models\Finding;
+use App\Models\Tenant;
+use Filament\Facades\Filament;
+use Filament\Widgets\Widget;
+
+class BaselineCompareNow extends Widget
+{
+    protected static bool $isLazy = false;
+
+    protected string $view = 'filament.widgets.dashboard.baseline-compare-now';
+
+    /**
+     * @return array<string, mixed>
+     */
+    protected function getViewData(): array
+    {
+        $tenant = Filament::getTenant();
+
+        if (! $tenant instanceof Tenant) {
+            return [
+                'hasAssignment' => false,
+                'profileName' => null,
+                'findingsCount' => 0,
+                'highCount' => 0,
+                'landingUrl' => null,
+            ];
+        }
+
+        $assignment = BaselineTenantAssignment::query()
+            ->where('tenant_id', $tenant->getKey())
+            ->with('baselineProfile')
+            ->first();
+
+        if (! $assignment instanceof BaselineTenantAssignment || $assignment->baselineProfile === null) {
+            return [
+                'hasAssignment' => false,
+                'profileName' => null,
+                'findingsCount' => 0,
+                'highCount' => 0,
+                'landingUrl' => null,
+            ];
+        }
+
+        $profile = $assignment->baselineProfile;
+        $scopeKey = 'baseline_profile:' . $profile->getKey();
+
+        $findingsQuery = Finding::query()
+            ->where('tenant_id', $tenant->getKey())
+            ->where('finding_type', Finding::FINDING_TYPE_DRIFT)
+            ->where('source', 'baseline.compare')
+            ->where('scope_key', $scopeKey)
+            ->where('status', Finding::STATUS_NEW);
+
+        $findingsCount = (int) (clone $findingsQuery)->count();
+        $highCount = (int) (clone $findingsQuery)
+            ->where('severity', Finding::SEVERITY_HIGH)
+            ->count();
+
+        return [
+            'hasAssignment' => true,
+            'profileName' => (string) $profile->name,
+            'findingsCount' => $findingsCount,
+            'highCount' => $highCount,
+            'landingUrl' => \App\Filament\Pages\BaselineCompareLanding::getUrl(tenant: $tenant),
+        ];
+    }
+}
diff --git a/app/Jobs/CaptureBaselineSnapshotJob.php b/app/Jobs/CaptureBaselineSnapshotJob.php
new file mode 100644
index 0000000..7909911
--- /dev/null
+++ b/app/Jobs/CaptureBaselineSnapshotJob.php
@@ -0,0 +1,285 @@
+<?php
+
+namespace App\Jobs;
+
+use App\Jobs\Middleware\TrackOperationRun;
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshot;
+use App\Models\BaselineSnapshotItem;
+use App\Models\InventoryItem;
+use App\Models\OperationRun;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\Baselines\BaselineSnapshotIdentity;
+use App\Services\Intune\AuditLogger;
+use App\Services\OperationRunService;
+use App\Support\Baselines\BaselineScope;
+use App\Support\OperationRunOutcome;
+use App\Support\OperationRunStatus;
+use Illuminate\Bus\Queueable;
+use Illuminate\Contracts\Queue\ShouldQueue;
+use Illuminate\Foundation\Bus\Dispatchable;
+use Illuminate\Queue\InteractsWithQueue;
+use Illuminate\Queue\SerializesModels;
+use RuntimeException;
+
+class CaptureBaselineSnapshotJob implements ShouldQueue
+{
+    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
+
+    public ?OperationRun $operationRun = null;
+
+    public function __construct(
+        public OperationRun $run,
+    ) {
+        $this->operationRun = $run;
+    }
+
+    /**
+     * @return array<int, object>
+     */
+    public function middleware(): array
+    {
+        return [new TrackOperationRun];
+    }
+
+    public function handle(
+        BaselineSnapshotIdentity $identity,
+        AuditLogger $auditLogger,
+        OperationRunService $operationRunService,
+    ): void {
+        if (! $this->operationRun instanceof OperationRun) {
+            $this->fail(new RuntimeException('OperationRun context is required for CaptureBaselineSnapshotJob.'));
+
+            return;
+        }
+
+        $context = is_array($this->operationRun->context) ? $this->operationRun->context : [];
+        $profileId = (int) ($context['baseline_profile_id'] ?? 0);
+        $sourceTenantId = (int) ($context['source_tenant_id'] ?? 0);
+
+        $profile = BaselineProfile::query()->find($profileId);
+
+        if (! $profile instanceof BaselineProfile) {
+            throw new RuntimeException("BaselineProfile #{$profileId} not found.");
+        }
+
+        $sourceTenant = Tenant::query()->find($sourceTenantId);
+
+        if (! $sourceTenant instanceof Tenant) {
+            throw new RuntimeException("Source Tenant #{$sourceTenantId} not found.");
+        }
+
+        $initiator = $this->operationRun->user_id
+            ? User::query()->find($this->operationRun->user_id)
+            : null;
+
+        $effectiveScope = BaselineScope::fromJsonb($context['effective_scope'] ?? null);
+
+        $this->auditStarted($auditLogger, $sourceTenant, $profile, $initiator);
+
+        $snapshotItems = $this->collectSnapshotItems($sourceTenant, $effectiveScope, $identity);
+
+        $identityHash = $identity->computeIdentity($snapshotItems);
+
+        $snapshot = $this->findOrCreateSnapshot(
+            $profile,
+            $identityHash,
+            $snapshotItems,
+        );
+
+        $wasNewSnapshot = $snapshot->wasRecentlyCreated;
+
+        if ($profile->status === BaselineProfile::STATUS_ACTIVE) {
+            $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+        }
+
+        $summaryCounts = [
+            'total' => count($snapshotItems),
+            'processed' => count($snapshotItems),
+            'succeeded' => count($snapshotItems),
+            'failed' => 0,
+        ];
+
+        $operationRunService->updateRun(
+            $this->operationRun,
+            status: OperationRunStatus::Completed->value,
+            outcome: OperationRunOutcome::Succeeded->value,
+            summaryCounts: $summaryCounts,
+        );
+
+        $updatedContext = is_array($this->operationRun->context) ? $this->operationRun->context : [];
+        $updatedContext['result'] = [
+            'snapshot_id' => (int) $snapshot->getKey(),
+            'snapshot_identity_hash' => $identityHash,
+            'was_new_snapshot' => $wasNewSnapshot,
+            'items_captured' => count($snapshotItems),
+        ];
+        $this->operationRun->update(['context' => $updatedContext]);
+
+        $this->auditCompleted($auditLogger, $sourceTenant, $profile, $snapshot, $initiator, $snapshotItems);
+    }
+
+    /**
+     * @return array<int, array{subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string, meta_jsonb: array<string, mixed>}>
+     */
+    private function collectSnapshotItems(
+        Tenant $sourceTenant,
+        BaselineScope $scope,
+        BaselineSnapshotIdentity $identity,
+    ): array {
+        $query = InventoryItem::query()
+            ->where('tenant_id', $sourceTenant->getKey());
+
+        if (! $scope->isEmpty()) {
+            $query->whereIn('policy_type', $scope->policyTypes);
+        }
+
+        $items = [];
+
+        $query->orderBy('policy_type')
+            ->orderBy('external_id')
+            ->chunk(500, function ($inventoryItems) use (&$items, $identity): void {
+                foreach ($inventoryItems as $inventoryItem) {
+                    $metaJsonb = is_array($inventoryItem->meta_jsonb) ? $inventoryItem->meta_jsonb : [];
+                    $baselineHash = $identity->hashItemContent($metaJsonb);
+
+                    $items[] = [
+                        'subject_type' => 'policy',
+                        'subject_external_id' => (string) $inventoryItem->external_id,
+                        'policy_type' => (string) $inventoryItem->policy_type,
+                        'baseline_hash' => $baselineHash,
+                        'meta_jsonb' => [
+                            'display_name' => $inventoryItem->display_name,
+                            'category' => $inventoryItem->category,
+                            'platform' => $inventoryItem->platform,
+                        ],
+                    ];
+                }
+            });
+
+        return $items;
+    }
+
+    /**
+     * @param  array<int, array{subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string, meta_jsonb: array<string, mixed>}>  $snapshotItems
+     */
+    private function findOrCreateSnapshot(
+        BaselineProfile $profile,
+        string $identityHash,
+        array $snapshotItems,
+    ): BaselineSnapshot {
+        $existing = BaselineSnapshot::query()
+            ->where('workspace_id', $profile->workspace_id)
+            ->where('baseline_profile_id', $profile->getKey())
+            ->where('snapshot_identity_hash', $identityHash)
+            ->first();
+
+        if ($existing instanceof BaselineSnapshot) {
+            return $existing;
+        }
+
+        $snapshot = BaselineSnapshot::create([
+            'workspace_id' => (int) $profile->workspace_id,
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'snapshot_identity_hash' => $identityHash,
+            'captured_at' => now(),
+            'summary_jsonb' => [
+                'total_items' => count($snapshotItems),
+                'policy_type_counts' => $this->countByPolicyType($snapshotItems),
+            ],
+        ]);
+
+        foreach (array_chunk($snapshotItems, 100) as $chunk) {
+            $rows = array_map(
+                fn (array $item): array => [
+                    'baseline_snapshot_id' => (int) $snapshot->getKey(),
+                    'subject_type' => $item['subject_type'],
+                    'subject_external_id' => $item['subject_external_id'],
+                    'policy_type' => $item['policy_type'],
+                    'baseline_hash' => $item['baseline_hash'],
+                    'meta_jsonb' => json_encode($item['meta_jsonb']),
+                    'created_at' => now(),
+                    'updated_at' => now(),
+                ],
+                $chunk,
+            );
+
+            BaselineSnapshotItem::insert($rows);
+        }
+
+        return $snapshot;
+    }
+
+    /**
+     * @param  array<int, array{policy_type: string}>  $items
+     * @return array<string, int>
+     */
+    private function countByPolicyType(array $items): array
+    {
+        $counts = [];
+
+        foreach ($items as $item) {
+            $type = (string) $item['policy_type'];
+            $counts[$type] = ($counts[$type] ?? 0) + 1;
+        }
+
+        ksort($counts);
+
+        return $counts;
+    }
+
+    private function auditStarted(
+        AuditLogger $auditLogger,
+        Tenant $tenant,
+        BaselineProfile $profile,
+        ?User $initiator,
+    ): void {
+        $auditLogger->log(
+            tenant: $tenant,
+            action: 'baseline.capture.started',
+            context: [
+                'metadata' => [
+                    'operation_run_id' => (int) $this->operationRun->getKey(),
+                    'baseline_profile_id' => (int) $profile->getKey(),
+                    'baseline_profile_name' => (string) $profile->name,
+                ],
+            ],
+            actorId: $initiator?->id,
+            actorEmail: $initiator?->email,
+            actorName: $initiator?->name,
+            resourceType: 'baseline_profile',
+            resourceId: (string) $profile->getKey(),
+        );
+    }
+
+    private function auditCompleted(
+        AuditLogger $auditLogger,
+        Tenant $tenant,
+        BaselineProfile $profile,
+        BaselineSnapshot $snapshot,
+        ?User $initiator,
+        array $snapshotItems,
+    ): void {
+        $auditLogger->log(
+            tenant: $tenant,
+            action: 'baseline.capture.completed',
+            context: [
+                'metadata' => [
+                    'operation_run_id' => (int) $this->operationRun->getKey(),
+                    'baseline_profile_id' => (int) $profile->getKey(),
+                    'baseline_profile_name' => (string) $profile->name,
+                    'snapshot_id' => (int) $snapshot->getKey(),
+                    'snapshot_identity_hash' => (string) $snapshot->snapshot_identity_hash,
+                    'items_captured' => count($snapshotItems),
+                    'was_new_snapshot' => $snapshot->wasRecentlyCreated,
+                ],
+            ],
+            actorId: $initiator?->id,
+            actorEmail: $initiator?->email,
+            actorName: $initiator?->name,
+            resourceType: 'operation_run',
+            resourceId: (string) $this->operationRun->getKey(),
+        );
+    }
+}
diff --git a/app/Jobs/CompareBaselineToTenantJob.php b/app/Jobs/CompareBaselineToTenantJob.php
new file mode 100644
index 0000000..2d0cb1b
--- /dev/null
+++ b/app/Jobs/CompareBaselineToTenantJob.php
@@ -0,0 +1,394 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Jobs;
+
+use App\Jobs\Middleware\TrackOperationRun;
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshotItem;
+use App\Models\Finding;
+use App\Models\InventoryItem;
+use App\Models\OperationRun;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\Baselines\BaselineSnapshotIdentity;
+use App\Services\Drift\DriftHasher;
+use App\Services\Intune\AuditLogger;
+use App\Services\OperationRunService;
+use App\Support\Baselines\BaselineScope;
+use App\Support\OperationRunOutcome;
+use App\Support\OperationRunStatus;
+use Illuminate\Bus\Queueable;
+use Illuminate\Contracts\Queue\ShouldQueue;
+use Illuminate\Foundation\Bus\Dispatchable;
+use Illuminate\Queue\InteractsWithQueue;
+use Illuminate\Queue\SerializesModels;
+use RuntimeException;
+
+class CompareBaselineToTenantJob implements ShouldQueue
+{
+    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
+
+    public ?OperationRun $operationRun = null;
+
+    public function __construct(
+        public OperationRun $run,
+    ) {
+        $this->operationRun = $run;
+    }
+
+    /**
+     * @return array<int, object>
+     */
+    public function middleware(): array
+    {
+        return [new TrackOperationRun];
+    }
+
+    public function handle(
+        DriftHasher $driftHasher,
+        BaselineSnapshotIdentity $snapshotIdentity,
+        AuditLogger $auditLogger,
+        OperationRunService $operationRunService,
+    ): void {
+        if (! $this->operationRun instanceof OperationRun) {
+            $this->fail(new RuntimeException('OperationRun context is required for CompareBaselineToTenantJob.'));
+
+            return;
+        }
+
+        $context = is_array($this->operationRun->context) ? $this->operationRun->context : [];
+        $profileId = (int) ($context['baseline_profile_id'] ?? 0);
+        $snapshotId = (int) ($context['baseline_snapshot_id'] ?? 0);
+
+        $profile = BaselineProfile::query()->find($profileId);
+
+        if (! $profile instanceof BaselineProfile) {
+            throw new RuntimeException("BaselineProfile #{$profileId} not found.");
+        }
+
+        $tenant = Tenant::query()->find($this->operationRun->tenant_id);
+
+        if (! $tenant instanceof Tenant) {
+            throw new RuntimeException("Tenant #{$this->operationRun->tenant_id} not found.");
+        }
+
+        $initiator = $this->operationRun->user_id
+            ? User::query()->find($this->operationRun->user_id)
+            : null;
+
+        $effectiveScope = BaselineScope::fromJsonb($context['effective_scope'] ?? null);
+        $scopeKey = 'baseline_profile:' . $profile->getKey();
+
+        $this->auditStarted($auditLogger, $tenant, $profile, $initiator);
+
+        $baselineItems = $this->loadBaselineItems($snapshotId);
+        $currentItems = $this->loadCurrentInventory($tenant, $effectiveScope, $snapshotIdentity);
+
+        $driftResults = $this->computeDrift($baselineItems, $currentItems);
+
+        $upsertedCount = $this->upsertFindings(
+            $driftHasher,
+            $tenant,
+            $profile,
+            $scopeKey,
+            $driftResults,
+        );
+
+        $severityBreakdown = $this->countBySeverity($driftResults);
+
+        $summaryCounts = [
+            'total' => count($driftResults),
+            'processed' => count($driftResults),
+            'succeeded' => $upsertedCount,
+            'failed' => count($driftResults) - $upsertedCount,
+            'high' => $severityBreakdown[Finding::SEVERITY_HIGH] ?? 0,
+            'medium' => $severityBreakdown[Finding::SEVERITY_MEDIUM] ?? 0,
+            'low' => $severityBreakdown[Finding::SEVERITY_LOW] ?? 0,
+        ];
+
+        $operationRunService->updateRun(
+            $this->operationRun,
+            status: OperationRunStatus::Completed->value,
+            outcome: OperationRunOutcome::Succeeded->value,
+            summaryCounts: $summaryCounts,
+        );
+
+        $updatedContext = is_array($this->operationRun->context) ? $this->operationRun->context : [];
+        $updatedContext['result'] = [
+            'findings_total' => count($driftResults),
+            'findings_upserted' => $upsertedCount,
+            'severity_breakdown' => $severityBreakdown,
+        ];
+        $this->operationRun->update(['context' => $updatedContext]);
+
+        $this->auditCompleted($auditLogger, $tenant, $profile, $initiator, $summaryCounts);
+    }
+
+    /**
+     * Load baseline snapshot items keyed by "policy_type|subject_external_id".
+     *
+     * @return array<string, array{subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string, meta_jsonb: array<string, mixed>}>
+     */
+    private function loadBaselineItems(int $snapshotId): array
+    {
+        $items = [];
+
+        BaselineSnapshotItem::query()
+            ->where('baseline_snapshot_id', $snapshotId)
+            ->orderBy('id')
+            ->chunk(500, function ($snapshotItems) use (&$items): void {
+                foreach ($snapshotItems as $item) {
+                    $key = $item->policy_type . '|' . $item->subject_external_id;
+                    $items[$key] = [
+                        'subject_type' => (string) $item->subject_type,
+                        'subject_external_id' => (string) $item->subject_external_id,
+                        'policy_type' => (string) $item->policy_type,
+                        'baseline_hash' => (string) $item->baseline_hash,
+                        'meta_jsonb' => is_array($item->meta_jsonb) ? $item->meta_jsonb : [],
+                    ];
+                }
+            });
+
+        return $items;
+    }
+
+    /**
+     * Load current inventory items keyed by "policy_type|external_id".
+     *
+     * @return array<string, array{subject_external_id: string, policy_type: string, current_hash: string, meta_jsonb: array<string, mixed>}>
+     */
+    private function loadCurrentInventory(
+        Tenant $tenant,
+        BaselineScope $scope,
+        BaselineSnapshotIdentity $snapshotIdentity,
+    ): array {
+        $query = InventoryItem::query()
+            ->where('tenant_id', $tenant->getKey());
+
+        if (! $scope->isEmpty()) {
+            $query->whereIn('policy_type', $scope->policyTypes);
+        }
+
+        $items = [];
+
+        $query->orderBy('policy_type')
+            ->orderBy('external_id')
+            ->chunk(500, function ($inventoryItems) use (&$items, $snapshotIdentity): void {
+                foreach ($inventoryItems as $inventoryItem) {
+                    $metaJsonb = is_array($inventoryItem->meta_jsonb) ? $inventoryItem->meta_jsonb : [];
+                    $currentHash = $snapshotIdentity->hashItemContent($metaJsonb);
+
+                    $key = $inventoryItem->policy_type . '|' . $inventoryItem->external_id;
+                    $items[$key] = [
+                        'subject_external_id' => (string) $inventoryItem->external_id,
+                        'policy_type' => (string) $inventoryItem->policy_type,
+                        'current_hash' => $currentHash,
+                        'meta_jsonb' => [
+                            'display_name' => $inventoryItem->display_name,
+                            'category' => $inventoryItem->category,
+                            'platform' => $inventoryItem->platform,
+                        ],
+                    ];
+                }
+            });
+
+        return $items;
+    }
+
+    /**
+     * Compare baseline items vs current inventory and produce drift results.
+     *
+     * @param  array<string, array{subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string, meta_jsonb: array<string, mixed>}>  $baselineItems
+     * @param  array<string, array{subject_external_id: string, policy_type: string, current_hash: string, meta_jsonb: array<string, mixed>}>  $currentItems
+     * @return array<int, array{change_type: string, severity: string, subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string, current_hash: string, evidence: array<string, mixed>}>
+     */
+    private function computeDrift(array $baselineItems, array $currentItems): array
+    {
+        $drift = [];
+
+        foreach ($baselineItems as $key => $baselineItem) {
+            if (! array_key_exists($key, $currentItems)) {
+                $drift[] = [
+                    'change_type' => 'missing_policy',
+                    'severity' => Finding::SEVERITY_HIGH,
+                    'subject_type' => $baselineItem['subject_type'],
+                    'subject_external_id' => $baselineItem['subject_external_id'],
+                    'policy_type' => $baselineItem['policy_type'],
+                    'baseline_hash' => $baselineItem['baseline_hash'],
+                    'current_hash' => '',
+                    'evidence' => [
+                        'change_type' => 'missing_policy',
+                        'policy_type' => $baselineItem['policy_type'],
+                        'display_name' => $baselineItem['meta_jsonb']['display_name'] ?? null,
+                    ],
+                ];
+
+                continue;
+            }
+
+            $currentItem = $currentItems[$key];
+
+            if ($baselineItem['baseline_hash'] !== $currentItem['current_hash']) {
+                $drift[] = [
+                    'change_type' => 'different_version',
+                    'severity' => Finding::SEVERITY_MEDIUM,
+                    'subject_type' => $baselineItem['subject_type'],
+                    'subject_external_id' => $baselineItem['subject_external_id'],
+                    'policy_type' => $baselineItem['policy_type'],
+                    'baseline_hash' => $baselineItem['baseline_hash'],
+                    'current_hash' => $currentItem['current_hash'],
+                    'evidence' => [
+                        'change_type' => 'different_version',
+                        'policy_type' => $baselineItem['policy_type'],
+                        'display_name' => $baselineItem['meta_jsonb']['display_name'] ?? null,
+                        'baseline_hash' => $baselineItem['baseline_hash'],
+                        'current_hash' => $currentItem['current_hash'],
+                    ],
+                ];
+            }
+        }
+
+        foreach ($currentItems as $key => $currentItem) {
+            if (! array_key_exists($key, $baselineItems)) {
+                $drift[] = [
+                    'change_type' => 'unexpected_policy',
+                    'severity' => Finding::SEVERITY_LOW,
+                    'subject_type' => 'policy',
+                    'subject_external_id' => $currentItem['subject_external_id'],
+                    'policy_type' => $currentItem['policy_type'],
+                    'baseline_hash' => '',
+                    'current_hash' => $currentItem['current_hash'],
+                    'evidence' => [
+                        'change_type' => 'unexpected_policy',
+                        'policy_type' => $currentItem['policy_type'],
+                        'display_name' => $currentItem['meta_jsonb']['display_name'] ?? null,
+                    ],
+                ];
+            }
+        }
+
+        return $drift;
+    }
+
+    /**
+     * Upsert drift findings using stable fingerprints.
+     *
+     * @param  array<int, array{change_type: string, severity: string, subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string, current_hash: string, evidence: array<string, mixed>}>  $driftResults
+     */
+    private function upsertFindings(
+        DriftHasher $driftHasher,
+        Tenant $tenant,
+        BaselineProfile $profile,
+        string $scopeKey,
+        array $driftResults,
+    ): int {
+        $upsertedCount = 0;
+        $tenantId = (int) $tenant->getKey();
+
+        foreach ($driftResults as $driftItem) {
+            $fingerprint = $driftHasher->fingerprint(
+                tenantId: $tenantId,
+                scopeKey: $scopeKey,
+                subjectType: $driftItem['subject_type'],
+                subjectExternalId: $driftItem['subject_external_id'],
+                changeType: $driftItem['change_type'],
+                baselineHash: $driftItem['baseline_hash'],
+                currentHash: $driftItem['current_hash'],
+            );
+
+            Finding::query()->updateOrCreate(
+                [
+                    'tenant_id' => $tenantId,
+                    'fingerprint' => $fingerprint,
+                ],
+                [
+                    'finding_type' => Finding::FINDING_TYPE_DRIFT,
+                    'source' => 'baseline.compare',
+                    'scope_key' => $scopeKey,
+                    'subject_type' => $driftItem['subject_type'],
+                    'subject_external_id' => $driftItem['subject_external_id'],
+                    'severity' => $driftItem['severity'],
+                    'status' => Finding::STATUS_NEW,
+                    'evidence_jsonb' => $driftItem['evidence'],
+                    'baseline_operation_run_id' => null,
+                    'current_operation_run_id' => (int) $this->operationRun->getKey(),
+                ],
+            );
+
+            $upsertedCount++;
+        }
+
+        return $upsertedCount;
+    }
+
+    /**
+     * @param  array<int, array{severity: string}>  $driftResults
+     * @return array<string, int>
+     */
+    private function countBySeverity(array $driftResults): array
+    {
+        $counts = [];
+
+        foreach ($driftResults as $item) {
+            $severity = $item['severity'];
+            $counts[$severity] = ($counts[$severity] ?? 0) + 1;
+        }
+
+        return $counts;
+    }
+
+    private function auditStarted(
+        AuditLogger $auditLogger,
+        Tenant $tenant,
+        BaselineProfile $profile,
+        ?User $initiator,
+    ): void {
+        $auditLogger->log(
+            tenant: $tenant,
+            action: 'baseline.compare.started',
+            context: [
+                'metadata' => [
+                    'operation_run_id' => (int) $this->operationRun->getKey(),
+                    'baseline_profile_id' => (int) $profile->getKey(),
+                    'baseline_profile_name' => (string) $profile->name,
+                ],
+            ],
+            actorId: $initiator?->id,
+            actorEmail: $initiator?->email,
+            actorName: $initiator?->name,
+            resourceType: 'baseline_profile',
+            resourceId: (string) $profile->getKey(),
+        );
+    }
+
+    private function auditCompleted(
+        AuditLogger $auditLogger,
+        Tenant $tenant,
+        BaselineProfile $profile,
+        ?User $initiator,
+        array $summaryCounts,
+    ): void {
+        $auditLogger->log(
+            tenant: $tenant,
+            action: 'baseline.compare.completed',
+            context: [
+                'metadata' => [
+                    'operation_run_id' => (int) $this->operationRun->getKey(),
+                    'baseline_profile_id' => (int) $profile->getKey(),
+                    'baseline_profile_name' => (string) $profile->name,
+                    'findings_total' => $summaryCounts['total'] ?? 0,
+                    'high' => $summaryCounts['high'] ?? 0,
+                    'medium' => $summaryCounts['medium'] ?? 0,
+                    'low' => $summaryCounts['low'] ?? 0,
+                ],
+            ],
+            actorId: $initiator?->id,
+            actorEmail: $initiator?->email,
+            actorName: $initiator?->name,
+            resourceType: 'operation_run',
+            resourceId: (string) $this->operationRun->getKey(),
+        );
+    }
+}
diff --git a/app/Models/BaselineProfile.php b/app/Models/BaselineProfile.php
new file mode 100644
index 0000000..27abca8
--- /dev/null
+++ b/app/Models/BaselineProfile.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+
+class BaselineProfile extends Model
+{
+    use HasFactory;
+
+    public const string STATUS_DRAFT = 'draft';
+
+    public const string STATUS_ACTIVE = 'active';
+
+    public const string STATUS_ARCHIVED = 'archived';
+
+    protected $guarded = [];
+
+    protected $casts = [
+        'scope_jsonb' => 'array',
+    ];
+
+    public function workspace(): BelongsTo
+    {
+        return $this->belongsTo(Workspace::class);
+    }
+
+    public function createdByUser(): BelongsTo
+    {
+        return $this->belongsTo(User::class, 'created_by_user_id');
+    }
+
+    public function activeSnapshot(): BelongsTo
+    {
+        return $this->belongsTo(BaselineSnapshot::class, 'active_snapshot_id');
+    }
+
+    public function snapshots(): HasMany
+    {
+        return $this->hasMany(BaselineSnapshot::class);
+    }
+
+    public function tenantAssignments(): HasMany
+    {
+        return $this->hasMany(BaselineTenantAssignment::class);
+    }
+}
diff --git a/app/Models/BaselineSnapshot.php b/app/Models/BaselineSnapshot.php
new file mode 100644
index 0000000..70aa411
--- /dev/null
+++ b/app/Models/BaselineSnapshot.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+
+class BaselineSnapshot extends Model
+{
+    use HasFactory;
+
+    protected $guarded = [];
+
+    protected $casts = [
+        'summary_jsonb' => 'array',
+        'captured_at' => 'datetime',
+    ];
+
+    public function workspace(): BelongsTo
+    {
+        return $this->belongsTo(Workspace::class);
+    }
+
+    public function baselineProfile(): BelongsTo
+    {
+        return $this->belongsTo(BaselineProfile::class);
+    }
+
+    public function items(): HasMany
+    {
+        return $this->hasMany(BaselineSnapshotItem::class);
+    }
+}
diff --git a/app/Models/BaselineSnapshotItem.php b/app/Models/BaselineSnapshotItem.php
new file mode 100644
index 0000000..29f1172
--- /dev/null
+++ b/app/Models/BaselineSnapshotItem.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class BaselineSnapshotItem extends Model
+{
+    use HasFactory;
+
+    protected $guarded = [];
+
+    protected $casts = [
+        'meta_jsonb' => 'array',
+    ];
+
+    public function snapshot(): BelongsTo
+    {
+        return $this->belongsTo(BaselineSnapshot::class, 'baseline_snapshot_id');
+    }
+}
diff --git a/app/Models/BaselineTenantAssignment.php b/app/Models/BaselineTenantAssignment.php
new file mode 100644
index 0000000..14a42bc
--- /dev/null
+++ b/app/Models/BaselineTenantAssignment.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace App\Models;
+
+use App\Support\Concerns\DerivesWorkspaceIdFromTenant;
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class BaselineTenantAssignment extends Model
+{
+    use DerivesWorkspaceIdFromTenant;
+    use HasFactory;
+
+    protected $guarded = [];
+
+    protected $casts = [
+        'override_scope_jsonb' => 'array',
+    ];
+
+    public function workspace(): BelongsTo
+    {
+        return $this->belongsTo(Workspace::class);
+    }
+
+    public function tenant(): BelongsTo
+    {
+        return $this->belongsTo(Tenant::class);
+    }
+
+    public function baselineProfile(): BelongsTo
+    {
+        return $this->belongsTo(BaselineProfile::class);
+    }
+
+    public function assignedByUser(): BelongsTo
+    {
+        return $this->belongsTo(User::class, 'assigned_by_user_id');
+    }
+}
diff --git a/app/Providers/Filament/AdminPanelProvider.php b/app/Providers/Filament/AdminPanelProvider.php
index 5196825..4a2d9be 100644
--- a/app/Providers/Filament/AdminPanelProvider.php
+++ b/app/Providers/Filament/AdminPanelProvider.php
@@ -12,6 +12,7 @@
 use App\Filament\Resources\AlertDeliveryResource;
 use App\Filament\Resources\AlertDestinationResource;
 use App\Filament\Resources\AlertRuleResource;
+use App\Filament\Resources\BaselineProfileResource;
 use App\Filament\Resources\InventoryItemResource;
 use App\Filament\Resources\PolicyResource;
 use App\Filament\Resources\ProviderConnectionResource;
@@ -151,6 +152,7 @@ public function panel(Panel $panel): Panel
                 AlertRuleResource::class,
                 AlertDeliveryResource::class,
                 WorkspaceResource::class,
+                BaselineProfileResource::class,
             ])
             ->discoverClusters(in: app_path('Filament/Clusters'), for: 'App\\Filament\\Clusters')
             ->discoverResources(in: app_path('Filament/Resources'), for: 'App\\Filament\\Resources')
diff --git a/app/Services/Auth/WorkspaceRoleCapabilityMap.php b/app/Services/Auth/WorkspaceRoleCapabilityMap.php
index 3257ee8..796fbc3 100644
--- a/app/Services/Auth/WorkspaceRoleCapabilityMap.php
+++ b/app/Services/Auth/WorkspaceRoleCapabilityMap.php
@@ -36,6 +36,8 @@ class WorkspaceRoleCapabilityMap
             Capabilities::WORKSPACE_SETTINGS_MANAGE,
             Capabilities::ALERTS_VIEW,
             Capabilities::ALERTS_MANAGE,
+            Capabilities::WORKSPACE_BASELINES_VIEW,
+            Capabilities::WORKSPACE_BASELINES_MANAGE,
         ],
 
         WorkspaceRole::Manager->value => [
@@ -54,6 +56,8 @@ class WorkspaceRoleCapabilityMap
             Capabilities::WORKSPACE_SETTINGS_MANAGE,
             Capabilities::ALERTS_VIEW,
             Capabilities::ALERTS_MANAGE,
+            Capabilities::WORKSPACE_BASELINES_VIEW,
+            Capabilities::WORKSPACE_BASELINES_MANAGE,
         ],
 
         WorkspaceRole::Operator->value => [
@@ -66,12 +70,14 @@ class WorkspaceRoleCapabilityMap
             Capabilities::WORKSPACE_MANAGED_TENANT_ONBOARD_BOOTSTRAP_BACKUP_BOOTSTRAP,
             Capabilities::WORKSPACE_SETTINGS_VIEW,
             Capabilities::ALERTS_VIEW,
+            Capabilities::WORKSPACE_BASELINES_VIEW,
         ],
 
         WorkspaceRole::Readonly->value => [
             Capabilities::WORKSPACE_VIEW,
             Capabilities::WORKSPACE_SETTINGS_VIEW,
             Capabilities::ALERTS_VIEW,
+            Capabilities::WORKSPACE_BASELINES_VIEW,
         ],
     ];
 
diff --git a/app/Services/Baselines/BaselineCaptureService.php b/app/Services/Baselines/BaselineCaptureService.php
new file mode 100644
index 0000000..f596176
--- /dev/null
+++ b/app/Services/Baselines/BaselineCaptureService.php
@@ -0,0 +1,79 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Services\Baselines;
+
+use App\Jobs\CaptureBaselineSnapshotJob;
+use App\Models\BaselineProfile;
+use App\Models\OperationRun;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\OperationRunService;
+use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\BaselineScope;
+
+final class BaselineCaptureService
+{
+    public function __construct(
+        private readonly OperationRunService $runs,
+    ) {}
+
+    /**
+     * @return array{ok: bool, run?: OperationRun, reason_code?: string}
+     */
+    public function startCapture(
+        BaselineProfile $profile,
+        Tenant $sourceTenant,
+        User $initiator,
+    ): array {
+        $precondition = $this->validatePreconditions($profile, $sourceTenant);
+
+        if ($precondition !== null) {
+            return ['ok' => false, 'reason_code' => $precondition];
+        }
+
+        $effectiveScope = BaselineScope::fromJsonb(
+            is_array($profile->scope_jsonb) ? $profile->scope_jsonb : null,
+        );
+
+        $context = [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'source_tenant_id' => (int) $sourceTenant->getKey(),
+            'effective_scope' => $effectiveScope->toJsonb(),
+        ];
+
+        $run = $this->runs->ensureRunWithIdentity(
+            tenant: $sourceTenant,
+            type: 'baseline_capture',
+            identityInputs: [
+                'baseline_profile_id' => (int) $profile->getKey(),
+            ],
+            context: $context,
+            initiator: $initiator,
+        );
+
+        if ($run->wasRecentlyCreated) {
+            CaptureBaselineSnapshotJob::dispatch($run);
+        }
+
+        return ['ok' => true, 'run' => $run];
+    }
+
+    private function validatePreconditions(BaselineProfile $profile, Tenant $sourceTenant): ?string
+    {
+        if ($profile->status !== BaselineProfile::STATUS_ACTIVE) {
+            return BaselineReasonCodes::CAPTURE_PROFILE_NOT_ACTIVE;
+        }
+
+        if ($sourceTenant->workspace_id === null) {
+            return BaselineReasonCodes::CAPTURE_MISSING_SOURCE_TENANT;
+        }
+
+        if ((int) $sourceTenant->workspace_id !== (int) $profile->workspace_id) {
+            return BaselineReasonCodes::CAPTURE_MISSING_SOURCE_TENANT;
+        }
+
+        return null;
+    }
+}
diff --git a/app/Services/Baselines/BaselineCompareService.php b/app/Services/Baselines/BaselineCompareService.php
new file mode 100644
index 0000000..a4cc940
--- /dev/null
+++ b/app/Services/Baselines/BaselineCompareService.php
@@ -0,0 +1,97 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Services\Baselines;
+
+use App\Jobs\CompareBaselineToTenantJob;
+use App\Models\BaselineProfile;
+use App\Models\BaselineTenantAssignment;
+use App\Models\OperationRun;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\OperationRunService;
+use App\Support\Baselines\BaselineReasonCodes;
+use App\Support\Baselines\BaselineScope;
+
+final class BaselineCompareService
+{
+    public function __construct(
+        private readonly OperationRunService $runs,
+    ) {}
+
+    /**
+     * @return array{ok: bool, run?: OperationRun, reason_code?: string}
+     */
+    public function startCompare(
+        Tenant $tenant,
+        User $initiator,
+    ): array {
+        $assignment = BaselineTenantAssignment::query()
+            ->where('workspace_id', $tenant->workspace_id)
+            ->where('tenant_id', $tenant->getKey())
+            ->first();
+
+        if (! $assignment instanceof BaselineTenantAssignment) {
+            return ['ok' => false, 'reason_code' => BaselineReasonCodes::COMPARE_NO_ASSIGNMENT];
+        }
+
+        $profile = BaselineProfile::query()->find($assignment->baseline_profile_id);
+
+        if (! $profile instanceof BaselineProfile) {
+            return ['ok' => false, 'reason_code' => BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE];
+        }
+
+        $precondition = $this->validatePreconditions($profile);
+
+        if ($precondition !== null) {
+            return ['ok' => false, 'reason_code' => $precondition];
+        }
+
+        $snapshotId = (int) $profile->active_snapshot_id;
+
+        $profileScope = BaselineScope::fromJsonb(
+            is_array($profile->scope_jsonb) ? $profile->scope_jsonb : null,
+        );
+        $overrideScope = $assignment->override_scope_jsonb !== null
+            ? BaselineScope::fromJsonb(is_array($assignment->override_scope_jsonb) ? $assignment->override_scope_jsonb : null)
+            : null;
+
+        $effectiveScope = BaselineScope::effective($profileScope, $overrideScope);
+
+        $context = [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => $snapshotId,
+            'effective_scope' => $effectiveScope->toJsonb(),
+        ];
+
+        $run = $this->runs->ensureRunWithIdentity(
+            tenant: $tenant,
+            type: 'baseline_compare',
+            identityInputs: [
+                'baseline_profile_id' => (int) $profile->getKey(),
+            ],
+            context: $context,
+            initiator: $initiator,
+        );
+
+        if ($run->wasRecentlyCreated) {
+            CompareBaselineToTenantJob::dispatch($run);
+        }
+
+        return ['ok' => true, 'run' => $run];
+    }
+
+    private function validatePreconditions(BaselineProfile $profile): ?string
+    {
+        if ($profile->status !== BaselineProfile::STATUS_ACTIVE) {
+            return BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE;
+        }
+
+        if ($profile->active_snapshot_id === null) {
+            return BaselineReasonCodes::COMPARE_NO_ACTIVE_SNAPSHOT;
+        }
+
+        return null;
+    }
+}
diff --git a/app/Services/Baselines/BaselineSnapshotIdentity.php b/app/Services/Baselines/BaselineSnapshotIdentity.php
new file mode 100644
index 0000000..c761f92
--- /dev/null
+++ b/app/Services/Baselines/BaselineSnapshotIdentity.php
@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Services\Baselines;
+
+use App\Services\Drift\DriftHasher;
+
+/**
+ * Computes the snapshot_identity_hash for baseline snapshot content dedupe.
+ *
+ * The identity hash is a sha256 over normalized snapshot items, enabling
+ * detection of "nothing changed" when capturing the same inventory state.
+ */
+final class BaselineSnapshotIdentity
+{
+    public function __construct(
+        private readonly DriftHasher $hasher,
+    ) {}
+
+    /**
+     * Compute identity hash over a set of snapshot items.
+     *
+     * Each item is represented as an associative array with:
+     * - subject_type, subject_external_id, policy_type, baseline_hash
+     *
+     * @param  array<int, array{subject_type: string, subject_external_id: string, policy_type: string, baseline_hash: string}>  $items
+     */
+    public function computeIdentity(array $items): string
+    {
+        if ($items === []) {
+            return hash('sha256', '[]');
+        }
+
+        $normalized = array_map(
+            fn (array $item): string => implode('|', [
+                trim((string) ($item['subject_type'] ?? '')),
+                trim((string) ($item['subject_external_id'] ?? '')),
+                trim((string) ($item['policy_type'] ?? '')),
+                trim((string) ($item['baseline_hash'] ?? '')),
+            ]),
+            $items,
+        );
+
+        sort($normalized, SORT_STRING);
+
+        return hash('sha256', implode("\n", $normalized));
+    }
+
+    /**
+     * Compute a stable content hash for a single inventory item's metadata.
+     *
+     * Strips volatile OData keys and normalizes for stable comparison.
+     */
+    public function hashItemContent(mixed $metaJsonb): string
+    {
+        return $this->hasher->hashNormalized($metaJsonb);
+    }
+}
diff --git a/app/Support/Audit/AuditActionId.php b/app/Support/Audit/AuditActionId.php
index 6a10bfb..fd6d8a6 100644
--- a/app/Support/Audit/AuditActionId.php
+++ b/app/Support/Audit/AuditActionId.php
@@ -46,4 +46,17 @@ enum AuditActionId: string
 
     case WorkspaceSettingUpdated = 'workspace_setting.updated';
     case WorkspaceSettingReset = 'workspace_setting.reset';
+
+    case BaselineProfileCreated = 'baseline_profile.created';
+    case BaselineProfileUpdated = 'baseline_profile.updated';
+    case BaselineProfileArchived = 'baseline_profile.archived';
+    case BaselineCaptureStarted = 'baseline_capture.started';
+    case BaselineCaptureCompleted = 'baseline_capture.completed';
+    case BaselineCaptureFailed = 'baseline_capture.failed';
+    case BaselineCompareStarted = 'baseline_compare.started';
+    case BaselineCompareCompleted = 'baseline_compare.completed';
+    case BaselineCompareFailed = 'baseline_compare.failed';
+    case BaselineAssignmentCreated = 'baseline_assignment.created';
+    case BaselineAssignmentUpdated = 'baseline_assignment.updated';
+    case BaselineAssignmentDeleted = 'baseline_assignment.deleted';
 }
diff --git a/app/Support/Auth/Capabilities.php b/app/Support/Auth/Capabilities.php
index 1046dd4..033e3ee 100644
--- a/app/Support/Auth/Capabilities.php
+++ b/app/Support/Auth/Capabilities.php
@@ -96,6 +96,11 @@ class Capabilities
 
     public const PROVIDER_RUN = 'provider.run';
 
+    // Workspace baselines (Golden Master governance)
+    public const WORKSPACE_BASELINES_VIEW = 'workspace_baselines.view';
+
+    public const WORKSPACE_BASELINES_MANAGE = 'workspace_baselines.manage';
+
     // Audit
     public const AUDIT_VIEW = 'audit.view';
 
diff --git a/app/Support/Badges/BadgeCatalog.php b/app/Support/Badges/BadgeCatalog.php
index e32fde5..6481460 100644
--- a/app/Support/Badges/BadgeCatalog.php
+++ b/app/Support/Badges/BadgeCatalog.php
@@ -39,6 +39,7 @@ final class BadgeCatalog
         BadgeDomain::VerificationReportOverall->value => Domains\VerificationReportOverallBadge::class,
         BadgeDomain::AlertDeliveryStatus->value => Domains\AlertDeliveryStatusBadge::class,
         BadgeDomain::AlertDestinationLastTestStatus->value => Domains\AlertDestinationLastTestStatusBadge::class,
+        BadgeDomain::BaselineProfileStatus->value => Domains\BaselineProfileStatusBadge::class,
     ];
 
     /**
diff --git a/app/Support/Badges/BadgeDomain.php b/app/Support/Badges/BadgeDomain.php
index 9ce4b34..6f8db9b 100644
--- a/app/Support/Badges/BadgeDomain.php
+++ b/app/Support/Badges/BadgeDomain.php
@@ -31,4 +31,5 @@ enum BadgeDomain: string
     case VerificationReportOverall = 'verification_report_overall';
     case AlertDeliveryStatus = 'alert_delivery_status';
     case AlertDestinationLastTestStatus = 'alert_destination_last_test_status';
+    case BaselineProfileStatus = 'baseline_profile_status';
 }
diff --git a/app/Support/Badges/Domains/BaselineProfileStatusBadge.php b/app/Support/Badges/Domains/BaselineProfileStatusBadge.php
new file mode 100644
index 0000000..bdc2945
--- /dev/null
+++ b/app/Support/Badges/Domains/BaselineProfileStatusBadge.php
@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Badges\Domains;
+
+use App\Models\BaselineProfile;
+use App\Support\Badges\BadgeCatalog;
+use App\Support\Badges\BadgeMapper;
+use App\Support\Badges\BadgeSpec;
+
+final class BaselineProfileStatusBadge implements BadgeMapper
+{
+    public function spec(mixed $value): BadgeSpec
+    {
+        $state = BadgeCatalog::normalizeState($value);
+
+        return match ($state) {
+            BaselineProfile::STATUS_DRAFT => new BadgeSpec('Draft', 'gray', 'heroicon-m-pencil-square'),
+            BaselineProfile::STATUS_ACTIVE => new BadgeSpec('Active', 'success', 'heroicon-m-check-circle'),
+            BaselineProfile::STATUS_ARCHIVED => new BadgeSpec('Archived', 'warning', 'heroicon-m-archive-box'),
+            default => BadgeSpec::unknown(),
+        };
+    }
+}
diff --git a/app/Support/Baselines/BaselineReasonCodes.php b/app/Support/Baselines/BaselineReasonCodes.php
new file mode 100644
index 0000000..0dabf27
--- /dev/null
+++ b/app/Support/Baselines/BaselineReasonCodes.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines;
+
+/**
+ * Stable reason codes for 422 precondition failures.
+ *
+ * These codes are returned in the response body when a baseline operation
+ * cannot start due to unmet preconditions. No OperationRun is created.
+ */
+final class BaselineReasonCodes
+{
+    public const string CAPTURE_MISSING_SOURCE_TENANT = 'baseline.capture.missing_source_tenant';
+
+    public const string CAPTURE_PROFILE_NOT_ACTIVE = 'baseline.capture.profile_not_active';
+
+    public const string COMPARE_NO_ASSIGNMENT = 'baseline.compare.no_assignment';
+
+    public const string COMPARE_PROFILE_NOT_ACTIVE = 'baseline.compare.profile_not_active';
+
+    public const string COMPARE_NO_ACTIVE_SNAPSHOT = 'baseline.compare.no_active_snapshot';
+}
diff --git a/app/Support/Baselines/BaselineScope.php b/app/Support/Baselines/BaselineScope.php
new file mode 100644
index 0000000..beefd98
--- /dev/null
+++ b/app/Support/Baselines/BaselineScope.php
@@ -0,0 +1,113 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Support\Baselines;
+
+/**
+ * Value object for baseline scope resolution.
+ *
+ * A scope defines which policy types are included in a baseline profile.
+ * An empty policy_types array means "all types" (no filter).
+ */
+final class BaselineScope
+{
+    /**
+     * @param  array<string>  $policyTypes
+     */
+    public function __construct(
+        public readonly array $policyTypes = [],
+    ) {}
+
+    /**
+     * Create from the scope_jsonb column value.
+     *
+     * @param  array<string, mixed>|null  $scopeJsonb
+     */
+    public static function fromJsonb(?array $scopeJsonb): self
+    {
+        if ($scopeJsonb === null) {
+            return new self;
+        }
+
+        $policyTypes = $scopeJsonb['policy_types'] ?? [];
+
+        return new self(
+            policyTypes: is_array($policyTypes) ? array_values(array_filter($policyTypes, 'is_string')) : [],
+        );
+    }
+
+    /**
+     * Normalize the effective scope by intersecting profile scope with an optional override.
+     *
+     * Override can only narrow the profile scope (subset enforcement).
+     * If the profile scope is empty (all types), the override becomes the effective scope.
+     * If the override is empty or null, the profile scope is used as-is.
+     */
+    public static function effective(self $profileScope, ?self $overrideScope): self
+    {
+        if ($overrideScope === null || $overrideScope->isEmpty()) {
+            return $profileScope;
+        }
+
+        if ($profileScope->isEmpty()) {
+            return $overrideScope;
+        }
+
+        $intersected = array_values(array_intersect($profileScope->policyTypes, $overrideScope->policyTypes));
+
+        return new self(policyTypes: $intersected);
+    }
+
+    /**
+     * An empty scope means "all types".
+     */
+    public function isEmpty(): bool
+    {
+        return $this->policyTypes === [];
+    }
+
+    /**
+     * Check if a policy type is included in this scope.
+     */
+    public function includes(string $policyType): bool
+    {
+        if ($this->isEmpty()) {
+            return true;
+        }
+
+        return in_array($policyType, $this->policyTypes, true);
+    }
+
+    /**
+     * Validate that override is a subset of the profile scope.
+     */
+    public static function isValidOverride(self $profileScope, self $overrideScope): bool
+    {
+        if ($overrideScope->isEmpty()) {
+            return true;
+        }
+
+        if ($profileScope->isEmpty()) {
+            return true;
+        }
+
+        foreach ($overrideScope->policyTypes as $type) {
+            if (! in_array($type, $profileScope->policyTypes, true)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function toJsonb(): array
+    {
+        return [
+            'policy_types' => $this->policyTypes,
+        ];
+    }
+}
diff --git a/app/Support/OperationCatalog.php b/app/Support/OperationCatalog.php
index c7ab739..a99b234 100644
--- a/app/Support/OperationCatalog.php
+++ b/app/Support/OperationCatalog.php
@@ -45,6 +45,8 @@ public static function labels(): array
             'policy_version.force_delete' => 'Delete policy versions',
             'alerts.evaluate' => 'Alerts evaluation',
             'alerts.deliver' => 'Alerts delivery',
+            'baseline_capture' => 'Baseline capture',
+            'baseline_compare' => 'Baseline compare',
         ];
     }
 
@@ -72,6 +74,8 @@ public static function expectedDurationSeconds(string $operationType): ?int
             'assignments.fetch', 'assignments.restore' => 60,
             'ops.reconcile_adapter_runs' => 120,
             'alerts.evaluate', 'alerts.deliver' => 120,
+            'baseline_capture' => 120,
+            'baseline_compare' => 120,
             default => null,
         };
     }
diff --git a/app/Support/OpsUx/OperationSummaryKeys.php b/app/Support/OpsUx/OperationSummaryKeys.php
index 0892dd6..7452a1f 100644
--- a/app/Support/OpsUx/OperationSummaryKeys.php
+++ b/app/Support/OpsUx/OperationSummaryKeys.php
@@ -24,6 +24,9 @@ public static function all(): array
             'deleted',
             'items',
             'tenants',
+            'high',
+            'medium',
+            'low',
         ];
     }
 }
diff --git a/database/factories/BaselineProfileFactory.php b/database/factories/BaselineProfileFactory.php
new file mode 100644
index 0000000..a9ae350
--- /dev/null
+++ b/database/factories/BaselineProfileFactory.php
@@ -0,0 +1,61 @@
+<?php
+
+namespace Database\Factories;
+
+use App\Models\BaselineProfile;
+use App\Models\User;
+use App\Models\Workspace;
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/**
+ * @extends Factory<BaselineProfile>
+ */
+class BaselineProfileFactory extends Factory
+{
+    protected $model = BaselineProfile::class;
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function definition(): array
+    {
+        return [
+            'workspace_id' => Workspace::factory(),
+            'name' => fake()->unique()->words(3, true),
+            'description' => fake()->optional()->sentence(),
+            'version_label' => fake()->optional()->numerify('v#.#'),
+            'status' => BaselineProfile::STATUS_DRAFT,
+            'scope_jsonb' => ['policy_types' => []],
+            'active_snapshot_id' => null,
+            'created_by_user_id' => null,
+        ];
+    }
+
+    public function active(): static
+    {
+        return $this->state(fn (): array => [
+            'status' => BaselineProfile::STATUS_ACTIVE,
+        ]);
+    }
+
+    public function archived(): static
+    {
+        return $this->state(fn (): array => [
+            'status' => BaselineProfile::STATUS_ARCHIVED,
+        ]);
+    }
+
+    public function withScope(array $policyTypes): static
+    {
+        return $this->state(fn (): array => [
+            'scope_jsonb' => ['policy_types' => $policyTypes],
+        ]);
+    }
+
+    public function createdBy(User $user): static
+    {
+        return $this->state(fn (): array => [
+            'created_by_user_id' => $user->getKey(),
+        ]);
+    }
+}
diff --git a/database/factories/BaselineSnapshotFactory.php b/database/factories/BaselineSnapshotFactory.php
new file mode 100644
index 0000000..dae6764
--- /dev/null
+++ b/database/factories/BaselineSnapshotFactory.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Database\Factories;
+
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshot;
+use App\Models\Workspace;
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/**
+ * @extends Factory<BaselineSnapshot>
+ */
+class BaselineSnapshotFactory extends Factory
+{
+    protected $model = BaselineSnapshot::class;
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function definition(): array
+    {
+        return [
+            'workspace_id' => Workspace::factory(),
+            'baseline_profile_id' => BaselineProfile::factory(),
+            'snapshot_identity_hash' => hash('sha256', fake()->uuid()),
+            'captured_at' => now(),
+            'summary_jsonb' => ['total_items' => 0],
+        ];
+    }
+}
diff --git a/database/factories/BaselineSnapshotItemFactory.php b/database/factories/BaselineSnapshotItemFactory.php
new file mode 100644
index 0000000..4c2216d
--- /dev/null
+++ b/database/factories/BaselineSnapshotItemFactory.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Database\Factories;
+
+use App\Models\BaselineSnapshot;
+use App\Models\BaselineSnapshotItem;
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/**
+ * @extends Factory<BaselineSnapshotItem>
+ */
+class BaselineSnapshotItemFactory extends Factory
+{
+    protected $model = BaselineSnapshotItem::class;
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function definition(): array
+    {
+        return [
+            'baseline_snapshot_id' => BaselineSnapshot::factory(),
+            'subject_type' => 'policy',
+            'subject_external_id' => fake()->uuid(),
+            'policy_type' => 'deviceConfiguration',
+            'baseline_hash' => hash('sha256', fake()->uuid()),
+            'meta_jsonb' => ['display_name' => fake()->words(3, true)],
+        ];
+    }
+}
diff --git a/database/factories/BaselineTenantAssignmentFactory.php b/database/factories/BaselineTenantAssignmentFactory.php
new file mode 100644
index 0000000..287d2d4
--- /dev/null
+++ b/database/factories/BaselineTenantAssignmentFactory.php
@@ -0,0 +1,31 @@
+<?php
+
+namespace Database\Factories;
+
+use App\Models\BaselineProfile;
+use App\Models\BaselineTenantAssignment;
+use App\Models\Tenant;
+use App\Models\Workspace;
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/**
+ * @extends Factory<BaselineTenantAssignment>
+ */
+class BaselineTenantAssignmentFactory extends Factory
+{
+    protected $model = BaselineTenantAssignment::class;
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function definition(): array
+    {
+        return [
+            'workspace_id' => Workspace::factory(),
+            'tenant_id' => Tenant::factory(),
+            'baseline_profile_id' => BaselineProfile::factory(),
+            'override_scope_jsonb' => null,
+            'assigned_by_user_id' => null,
+        ];
+    }
+}
diff --git a/database/migrations/2026_02_19_100001_create_baseline_profiles_table.php b/database/migrations/2026_02_19_100001_create_baseline_profiles_table.php
new file mode 100644
index 0000000..2bcf26e
--- /dev/null
+++ b/database/migrations/2026_02_19_100001_create_baseline_profiles_table.php
@@ -0,0 +1,32 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('baseline_profiles', function (Blueprint $table): void {
+            $table->id();
+            $table->foreignId('workspace_id')->constrained('workspaces')->cascadeOnDelete();
+            $table->string('name');
+            $table->text('description')->nullable();
+            $table->string('version_label')->nullable();
+            $table->string('status')->default('draft');
+            $table->jsonb('scope_jsonb');
+            $table->unsignedBigInteger('active_snapshot_id')->nullable();
+            $table->foreignId('created_by_user_id')->nullable()->constrained('users')->nullOnDelete();
+            $table->timestamps();
+
+            $table->index(['workspace_id', 'status']);
+            $table->unique(['workspace_id', 'name']);
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('baseline_profiles');
+    }
+};
diff --git a/database/migrations/2026_02_19_100002_create_baseline_snapshots_table.php b/database/migrations/2026_02_19_100002_create_baseline_snapshots_table.php
new file mode 100644
index 0000000..ab9d776
--- /dev/null
+++ b/database/migrations/2026_02_19_100002_create_baseline_snapshots_table.php
@@ -0,0 +1,40 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('baseline_snapshots', function (Blueprint $table): void {
+            $table->id();
+            $table->foreignId('workspace_id')->constrained('workspaces')->cascadeOnDelete();
+            $table->foreignId('baseline_profile_id')->constrained('baseline_profiles')->cascadeOnDelete();
+            $table->string('snapshot_identity_hash', 64);
+            $table->timestampTz('captured_at');
+            $table->jsonb('summary_jsonb')->nullable();
+            $table->timestamps();
+
+            $table->unique(['workspace_id', 'baseline_profile_id', 'snapshot_identity_hash'], 'baseline_snapshots_dedupe_unique');
+            $table->index(['workspace_id', 'baseline_profile_id', 'captured_at'], 'baseline_snapshots_lookup_idx');
+        });
+
+        Schema::table('baseline_profiles', function (Blueprint $table): void {
+            $table->foreign('active_snapshot_id')
+                ->references('id')
+                ->on('baseline_snapshots')
+                ->nullOnDelete();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('baseline_profiles', function (Blueprint $table): void {
+            $table->dropForeign(['active_snapshot_id']);
+        });
+
+        Schema::dropIfExists('baseline_snapshots');
+    }
+};
diff --git a/database/migrations/2026_02_19_100003_create_baseline_snapshot_items_table.php b/database/migrations/2026_02_19_100003_create_baseline_snapshot_items_table.php
new file mode 100644
index 0000000..ef6df08
--- /dev/null
+++ b/database/migrations/2026_02_19_100003_create_baseline_snapshot_items_table.php
@@ -0,0 +1,33 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('baseline_snapshot_items', function (Blueprint $table): void {
+            $table->id();
+            $table->foreignId('baseline_snapshot_id')->constrained('baseline_snapshots')->cascadeOnDelete();
+            $table->string('subject_type');
+            $table->string('subject_external_id');
+            $table->string('policy_type');
+            $table->string('baseline_hash', 64);
+            $table->jsonb('meta_jsonb')->nullable();
+            $table->timestamps();
+
+            $table->unique(
+                ['baseline_snapshot_id', 'subject_type', 'subject_external_id'],
+                'baseline_snapshot_items_subject_unique'
+            );
+            $table->index(['baseline_snapshot_id', 'policy_type'], 'baseline_snapshot_items_policy_type_idx');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('baseline_snapshot_items');
+    }
+};
diff --git a/database/migrations/2026_02_19_100004_create_baseline_tenant_assignments_table.php b/database/migrations/2026_02_19_100004_create_baseline_tenant_assignments_table.php
new file mode 100644
index 0000000..dcdd6bc
--- /dev/null
+++ b/database/migrations/2026_02_19_100004_create_baseline_tenant_assignments_table.php
@@ -0,0 +1,29 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('baseline_tenant_assignments', function (Blueprint $table): void {
+            $table->id();
+            $table->foreignId('workspace_id')->constrained('workspaces')->cascadeOnDelete();
+            $table->foreignId('tenant_id')->constrained('tenants')->cascadeOnDelete();
+            $table->foreignId('baseline_profile_id')->constrained('baseline_profiles')->cascadeOnDelete();
+            $table->jsonb('override_scope_jsonb')->nullable();
+            $table->foreignId('assigned_by_user_id')->nullable()->constrained('users')->nullOnDelete();
+            $table->timestamps();
+
+            $table->unique(['workspace_id', 'tenant_id']);
+            $table->index(['workspace_id', 'baseline_profile_id']);
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('baseline_tenant_assignments');
+    }
+};
diff --git a/database/migrations/2026_02_19_100005_add_source_to_findings_table.php b/database/migrations/2026_02_19_100005_add_source_to_findings_table.php
new file mode 100644
index 0000000..5071b39
--- /dev/null
+++ b/database/migrations/2026_02_19_100005_add_source_to_findings_table.php
@@ -0,0 +1,24 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('findings', function (Blueprint $table): void {
+            $table->string('source')->nullable()->after('finding_type');
+            $table->index(['tenant_id', 'source']);
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('findings', function (Blueprint $table): void {
+            $table->dropIndex(['tenant_id', 'source']);
+            $table->dropColumn('source');
+        });
+    }
+};
diff --git a/resources/views/filament/pages/baseline-compare-landing.blade.php b/resources/views/filament/pages/baseline-compare-landing.blade.php
new file mode 100644
index 0000000..d8bb3f1
--- /dev/null
+++ b/resources/views/filament/pages/baseline-compare-landing.blade.php
@@ -0,0 +1,93 @@
+<x-filament::page>
+    <x-filament::section>
+        <div class="flex flex-col gap-4">
+            <div class="text-sm text-gray-600 dark:text-gray-300">
+                Compare the current tenant state against the assigned baseline profile to detect drift.
+            </div>
+
+            @if (filled($profileName))
+                <div class="flex items-center gap-2 text-sm">
+                    <span class="font-medium text-gray-950 dark:text-white">Baseline Profile:</span>
+                    <span class="text-gray-700 dark:text-gray-200">{{ $profileName }}</span>
+                    @if ($snapshotId)
+                        <x-filament::badge color="success" size="sm">
+                            Snapshot #{{ $snapshotId }}
+                        </x-filament::badge>
+                    @endif
+                </div>
+            @endif
+
+            @if ($state === 'no_tenant')
+                <x-filament::badge color="gray">No tenant selected</x-filament::badge>
+                <div class="text-sm text-gray-500 dark:text-gray-400">{{ $message }}</div>
+            @elseif ($state === 'no_assignment')
+                <x-filament::badge color="gray">No baseline assigned</x-filament::badge>
+                <div class="text-sm text-gray-500 dark:text-gray-400">{{ $message }}</div>
+            @elseif ($state === 'no_snapshot')
+                <x-filament::badge color="warning">No snapshot available</x-filament::badge>
+                <div class="text-sm text-gray-500 dark:text-gray-400">{{ $message }}</div>
+            @elseif ($state === 'comparing')
+                <div class="flex items-center gap-2">
+                    <x-filament::badge color="info">Comparing…</x-filament::badge>
+                    <x-filament::loading-indicator class="h-4 w-4" />
+                </div>
+                <div class="text-sm text-gray-500 dark:text-gray-400">{{ $message }}</div>
+
+                @if ($this->getRunUrl())
+                    <x-filament::link :href="$this->getRunUrl()" size="sm">
+                        View operation run
+                    </x-filament::link>
+                @endif
+            @elseif ($state === 'idle')
+                <x-filament::badge color="gray">Ready to compare</x-filament::badge>
+                <div class="text-sm text-gray-500 dark:text-gray-400">{{ $message }}</div>
+            @elseif ($state === 'ready')
+                @if ($findingsCount !== null && $findingsCount > 0)
+                    <div class="flex flex-wrap items-center gap-2">
+                        <x-filament::badge color="danger" size="sm">
+                            {{ $findingsCount }} {{ Str::plural('finding', $findingsCount) }}
+                        </x-filament::badge>
+
+                        @if (($severityCounts['high'] ?? 0) > 0)
+                            <x-filament::badge color="danger" size="sm">
+                                {{ $severityCounts['high'] }} high
+                            </x-filament::badge>
+                        @endif
+
+                        @if (($severityCounts['medium'] ?? 0) > 0)
+                            <x-filament::badge color="warning" size="sm">
+                                {{ $severityCounts['medium'] }} medium
+                            </x-filament::badge>
+                        @endif
+
+                        @if (($severityCounts['low'] ?? 0) > 0)
+                            <x-filament::badge color="gray" size="sm">
+                                {{ $severityCounts['low'] }} low
+                            </x-filament::badge>
+                        @endif
+                    </div>
+
+                    @if ($this->getFindingsUrl())
+                        <x-filament::link :href="$this->getFindingsUrl()" size="sm">
+                            View findings
+                        </x-filament::link>
+                    @endif
+                @else
+                    <x-filament::badge color="success" size="sm">
+                        No drift detected
+                    </x-filament::badge>
+
+                    @if (filled($message))
+                        <div class="text-sm text-gray-500 dark:text-gray-400">{{ $message }}</div>
+                    @endif
+                @endif
+
+                @if ($this->getRunUrl())
+                    <x-filament::link :href="$this->getRunUrl()" size="sm">
+                        View last run
+                    </x-filament::link>
+                @endif
+            @endif
+        </div>
+    </x-filament::section>
+</x-filament::page>
diff --git a/resources/views/filament/widgets/dashboard/baseline-compare-now.blade.php b/resources/views/filament/widgets/dashboard/baseline-compare-now.blade.php
new file mode 100644
index 0000000..03fa817
--- /dev/null
+++ b/resources/views/filament/widgets/dashboard/baseline-compare-now.blade.php
@@ -0,0 +1,41 @@
+<div class="rounded-lg bg-white p-4 shadow-sm ring-1 ring-gray-950/5 dark:bg-gray-900 dark:ring-white/10">
+    <div class="flex flex-col gap-3">
+        <div class="text-base font-semibold text-gray-950 dark:text-white">
+            Soll vs Ist
+        </div>
+
+        @if (! $hasAssignment)
+            <div class="text-sm text-gray-500 dark:text-gray-400">
+                No baseline profile assigned yet.
+            </div>
+        @else
+            <div class="text-sm text-gray-600 dark:text-gray-300">
+                Baseline: <span class="font-medium">{{ $profileName }}</span>
+            </div>
+
+            @if ($findingsCount > 0)
+                <div class="flex flex-wrap items-center gap-2">
+                    <x-filament::badge color="danger" size="sm">
+                        {{ $findingsCount }} open {{ Str::plural('finding', $findingsCount) }}
+                    </x-filament::badge>
+
+                    @if ($highCount > 0)
+                        <x-filament::badge color="danger" size="sm">
+                            {{ $highCount }} high
+                        </x-filament::badge>
+                    @endif
+                </div>
+            @else
+                <x-filament::badge color="success" size="sm">
+                    No open drift
+                </x-filament::badge>
+            @endif
+
+            @if ($landingUrl)
+                <x-filament::link :href="$landingUrl" size="sm">
+                    Go to Soll vs Ist
+                </x-filament::link>
+            @endif
+        @endif
+    </div>
+</div>
diff --git a/specs/101-golden-master-baseline-governance-v1/checklists/requirements.md b/specs/101-golden-master-baseline-governance-v1/checklists/requirements.md
new file mode 100644
index 0000000..be0d1f2
--- /dev/null
+++ b/specs/101-golden-master-baseline-governance-v1/checklists/requirements.md
@@ -0,0 +1,50 @@
+# Specification Quality Checklist: Golden Master / Baseline Governance v1 (R1.1–R1.4)
+
+**Purpose**: Validate specification completeness and quality before proceeding to planning
+**Created**: 2026-02-19
+**Last Validated**: 2026-02-19 (post-analysis remediation)
+**Feature**: [spec.md](../spec.md)
+
+## Content Quality
+
+- [x] No implementation details (languages, frameworks, APIs)
+- [x] Focused on user value and business needs
+- [x] Written for non-technical stakeholders
+- [x] All mandatory sections completed
+
+## Requirement Completeness
+
+- [x] No [NEEDS CLARIFICATION] markers remain
+- [x] Requirements are testable and unambiguous
+- [x] Success criteria are measurable
+- [x] Success criteria are technology-agnostic (no implementation details)
+- [x] All acceptance scenarios are defined
+- [x] Edge cases are identified
+- [x] Scope is clearly bounded
+- [x] Dependencies and assumptions identified
+
+## Feature Readiness
+
+- [x] All functional requirements have clear acceptance criteria
+- [x] User scenarios cover primary flows
+- [x] Feature meets measurable outcomes defined in Success Criteria
+- [x] No implementation details leak into specification
+
+## Post-Analysis Remediation (2026-02-19)
+
+- [x] D1: Duplicate FR-003 removed (kept complete version with override clause)
+- [x] I1: Status lifecycle resolved — `draft ↔ active → archived` (deactivate = return to draft); spec.md + data-model.md aligned
+- [x] I3: "Delete" removed from UI Action Matrix — v1 is archive-only, no hard-delete
+- [x] C1: BadgeDomain task (T018a) added for BaselineProfileStatus badge compliance (BADGE-001)
+- [x] C2: Factory tasks (T018b) added for all 4 new models
+- [x] U1: `findings.source` default resolved — nullable, NULL default, legacy findings unaffected
+- [x] U2: Empty-scope edge case (EC-005) covered in T031 test description
+- [x] U3: Concurrent operation dedup (EC-004) covered in T032 + T040 test descriptions
+- [x] U4: T033 amended with explicit manage-capability gating via WorkspaceUiEnforcement
+- [x] U5: `scope_jsonb` schema defined in data-model.md (`{ "policy_types": [...] }`)
+- [x] E1: SC-001/SC-002 performance spot-check added to T060
+
+## Notes
+
+- All 12 analysis findings have been remediated
+- Task count updated: 60 → 62 (T018a, T018b added in Phase 2)
diff --git a/specs/101-golden-master-baseline-governance-v1/contracts/baseline-governance.openapi.yaml b/specs/101-golden-master-baseline-governance-v1/contracts/baseline-governance.openapi.yaml
new file mode 100644
index 0000000..c288211
--- /dev/null
+++ b/specs/101-golden-master-baseline-governance-v1/contracts/baseline-governance.openapi.yaml
@@ -0,0 +1,156 @@
+openapi: 3.0.3
+info:
+  title: Baseline Governance v1 (Golden Master)
+  version: 1.0.0
+  description: |
+    Conceptual HTTP contract for Baseline Governance actions.
+
+    Note: The implementation is Filament + Livewire; these endpoints describe the server-side behavior
+    (authorization, precondition failures, operation run creation) in a REST-like form for clarity.
+
+servers:
+  - url: /admin
+
+paths:
+  /workspaces/{workspaceId}/baselines:
+    get:
+      summary: List baseline profiles
+      parameters:
+        - $ref: '#/components/parameters/workspaceId'
+      responses:
+        '200':
+          description: OK
+
+  /workspaces/{workspaceId}/baselines/{baselineProfileId}:
+    get:
+      summary: View baseline profile
+      parameters:
+        - $ref: '#/components/parameters/workspaceId'
+        - $ref: '#/components/parameters/baselineProfileId'
+      responses:
+        '200':
+          description: OK
+        '404':
+          description: Not found (workspace not entitled)
+        '403':
+          description: Forbidden (missing capability)
+
+  /workspaces/{workspaceId}/baselines/{baselineProfileId}/capture:
+    post:
+      summary: Capture immutable baseline snapshot from a tenant
+      parameters:
+        - $ref: '#/components/parameters/workspaceId'
+        - $ref: '#/components/parameters/baselineProfileId'
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              required: [source_tenant_id]
+              properties:
+                source_tenant_id:
+                  type: integer
+      responses:
+        '202':
+          description: Enqueued (OperationRun created/reused)
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/OperationRunStartResponse'
+        '422':
+          description: Precondition failure (no OperationRun created)
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/PreconditionFailure'
+              examples:
+                missingSourceTenant:
+                  value:
+                    reason_code: baseline.capture.missing_source_tenant
+        '404':
+          description: Not found (workspace not entitled)
+        '403':
+          description: Forbidden (missing capability)
+
+  /tenants/{tenantId}/baseline-compare:
+    post:
+      summary: Compare tenant state to assigned baseline and generate drift findings
+      parameters:
+        - $ref: '#/components/parameters/tenantId'
+      responses:
+        '202':
+          description: Enqueued (OperationRun created/reused)
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/OperationRunStartResponse'
+        '422':
+          description: Precondition failure (no OperationRun created)
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/PreconditionFailure'
+              examples:
+                noAssignment:
+                  value:
+                    reason_code: baseline.compare.no_assignment
+                profileNotActive:
+                  value:
+                    reason_code: baseline.compare.profile_not_active
+                noActiveSnapshot:
+                  value:
+                    reason_code: baseline.compare.no_active_snapshot
+        '404':
+          description: Not found (tenant/workspace not entitled)
+        '403':
+          description: Forbidden (missing capability)
+
+  /tenants/{tenantId}/baseline-compare/latest:
+    get:
+      summary: Fetch latest baseline compare summary for tenant
+      parameters:
+        - $ref: '#/components/parameters/tenantId'
+      responses:
+        '200':
+          description: OK
+
+components:
+  parameters:
+    workspaceId:
+      name: workspaceId
+      in: path
+      required: true
+      schema:
+        type: integer
+    tenantId:
+      name: tenantId
+      in: path
+      required: true
+      schema:
+        type: integer
+    baselineProfileId:
+      name: baselineProfileId
+      in: path
+      required: true
+      schema:
+        type: integer
+
+  schemas:
+    OperationRunStartResponse:
+      type: object
+      required: [operation_run_id]
+      properties:
+        operation_run_id:
+          type: integer
+        reused:
+          type: boolean
+          description: True if an already-queued/running run was returned
+
+    PreconditionFailure:
+      type: object
+      required: [reason_code]
+      properties:
+        reason_code:
+          type: string
+          description: Stable code for UI + support triage
diff --git a/specs/101-golden-master-baseline-governance-v1/data-model.md b/specs/101-golden-master-baseline-governance-v1/data-model.md
new file mode 100644
index 0000000..f22c437
--- /dev/null
+++ b/specs/101-golden-master-baseline-governance-v1/data-model.md
@@ -0,0 +1,142 @@
+# Phase 1 — Data Model
+
+This is the proposed data model for **101 — Golden Master / Baseline Governance v1**.
+
+## Ownership Model
+
+- **Workspace-owned**
+  - Baseline profiles
+  - Baseline snapshots + snapshot items (data-minimized, reusable across tenants)
+
+- **Tenant-owned**
+  - Tenant assignments (joins a tenant to the workspace baseline standard)
+  - Operation runs for capture/compare
+  - Findings produced by compares
+
+This follows constitution SCOPE-001 conventions: tenant-owned tables include `workspace_id` + `tenant_id` NOT NULL; workspace-owned tables include `workspace_id` and do not include `tenant_id`.
+
+## Entities
+
+## 1) baseline_profiles (workspace-owned)
+
+**Purpose**: Defines the baseline (“what good looks like”) and its scope.
+
+**Fields**
+- `id` (pk)
+- `workspace_id` (fk workspaces, NOT NULL)
+- `name` (string, NOT NULL)
+- `description` (text, nullable)
+- `version_label` (string, nullable)
+- `status` (string enum: `draft|active|archived`, NOT NULL)
+- `scope_jsonb` (jsonb, NOT NULL)
+  - v1 schema: `{ "policy_types": ["string", ...] }` — array of policy type keys from `InventoryPolicyTypeMeta`
+  - An empty array means "all types" (no filtering); each string must be a known policy type key
+  - Future versions may add additional filter dimensions (e.g., `platforms`, `tags`)
+- `active_snapshot_id` (fk baseline_snapshots, nullable)
+- `created_by_user_id` (fk users, nullable)
+- timestamps
+
+**Indexes/constraints**
+- index: `(workspace_id, status)`
+- uniqueness: `(workspace_id, name)` (optional but recommended if UI expects names unique per workspace)
+
+**Validation notes**
+- status transitions: `draft ↔ active → archived` (archived is terminal in v1; deactivate returns active → draft)
+
+## 2) baseline_snapshots (workspace-owned)
+
+**Purpose**: Immutable baseline snapshot captured from a tenant.
+
+**Fields**
+- `id` (pk)
+- `workspace_id` (fk workspaces, NOT NULL)
+- `baseline_profile_id` (fk baseline_profiles, NOT NULL)
+- `snapshot_identity_hash` (string(64), NOT NULL)
+  - sha256 of normalized captured content
+- `captured_at` (timestamp tz, NOT NULL)
+- `summary_jsonb` (jsonb, nullable)
+  - counts/metadata (e.g., total items)
+- timestamps
+
+**Indexes/constraints**
+- unique: `(workspace_id, baseline_profile_id, snapshot_identity_hash)` (dedupe)
+- index: `(workspace_id, baseline_profile_id, captured_at desc)`
+
+## 3) baseline_snapshot_items (workspace-owned)
+
+**Purpose**: Immutable items within a snapshot.
+
+**Fields**
+- `id` (pk)
+- `baseline_snapshot_id` (fk baseline_snapshots, NOT NULL)
+- `subject_type` (string, NOT NULL) — e.g. `policy`
+- `subject_external_id` (string, NOT NULL) — stable key for the policy within the tenant inventory
+- `policy_type` (string, NOT NULL) — for filtering and summary
+- `baseline_hash` (string(64), NOT NULL) — stable content hash for the baseline version
+- `meta_jsonb` (jsonb, nullable) — minimized display metadata (no secrets)
+- timestamps
+
+**Indexes/constraints**
+- unique: `(baseline_snapshot_id, subject_type, subject_external_id)`
+- index: `(baseline_snapshot_id, policy_type)`
+
+## 4) baseline_tenant_assignments (tenant-owned)
+
+**Purpose**: Assigns exactly one baseline profile per tenant (v1), with optional scope override that can only narrow.
+
+**Fields**
+- `id` (pk)
+- `workspace_id` (fk workspaces, NOT NULL)
+- `tenant_id` (fk tenants, NOT NULL)
+- `baseline_profile_id` (fk baseline_profiles, NOT NULL)
+- `override_scope_jsonb` (jsonb, nullable)
+- `assigned_by_user_id` (fk users, nullable)
+- timestamps
+
+**Indexes/constraints**
+- unique: `(workspace_id, tenant_id)`
+- index: `(workspace_id, baseline_profile_id)`
+
+**Validation notes**
+- Override must be subset of profile scope (enforced server-side; store the final effective scope hash in the compare run context for traceability).
+
+## 5) findings additions (tenant-owned)
+
+**Purpose**: Persist baseline compare drift findings using existing findings system.
+
+**Required v1 additions**
+- add `findings.source` (string, **nullable**, default `NULL`)
+  - baseline compare uses `source='baseline.compare'`
+  - existing findings receive `NULL`; legacy drift-generate findings are queried with `whereNull('source')` or unconditionally
+- index: `(tenant_id, source)`
+
+**Baseline compare finding conventions**
+- `finding_type = 'drift'`
+- `scope_key = 'baseline_profile:<id>'`
+- `fingerprint = sha256(tenant_id|scope_key|subject_type|subject_external_id|change_type|baseline_hash|current_hash)` (using `DriftHasher`)
+- `evidence_jsonb` includes:
+  - `source` (until DB column exists)
+  - `baseline.profile_id`, `baseline.snapshot_id`
+  - `baseline.hash`, `current.hash`
+  - `change_type` (missing_policy|different_version|unexpected_policy)
+  - any minimized diff pointers required for UI
+
+## 6) operation_runs conventions
+
+**Operation types**
+- `baseline_capture`
+- `baseline_compare`
+
+**Run context** (json)
+- capture:
+  - `baseline_profile_id`
+  - `source_tenant_id`
+  - `effective_scope` / `selection_hash`
+- compare:
+  - `baseline_profile_id`
+  - `baseline_snapshot_id` (frozen at enqueue time)
+  - `effective_scope` / `selection_hash`
+
+**Summary counts**
+- compare should set a compact breakdown for dashboards:
+  - totals and severity breakdowns
diff --git a/specs/101-golden-master-baseline-governance-v1/plan.md b/specs/101-golden-master-baseline-governance-v1/plan.md
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@@ -0,0 +1,166 @@
+#+#+#+#+
+# Implementation Plan: Golden Master / Baseline Governance v1 (R1.1–R1.4)
+
+**Branch**: `101-golden-master-baseline-governance-v1` | **Date**: 2026-02-19 | **Spec**: [spec.md](spec.md)
+**Input**: Feature specification from [spec.md](spec.md)
+
+## Summary
+
+Implement a workspace-owned **Golden Master baseline** that can be captured from a tenant into an immutable snapshot, assigned to tenants, and compared (“Soll vs Ist”) to generate drift findings + a compact operational summary.
+
+This feature reuses existing patterns:
+- tenant-scoped `OperationRun` for capture/compare observability + idempotency
+- `findings` for drift tracking with sha256 fingerprints
+
+## Technical Context
+
+**Language/Version**: PHP 8.4.x
+**Framework**: Laravel 12
+**Admin UI**: Filament v5 (requires Livewire v4.0+)
+**Storage**: PostgreSQL (Sail locally); SQLite is used in some tests
+**Testing**: Pest v4 (`vendor/bin/sail artisan test`)
+**Target Platform**: Docker via Laravel Sail (macOS dev)
+**Project Type**: Laravel monolith (server-rendered Filament + Livewire)
+**Performance Goals**:
+- Compare completes within ~2 minutes for typical tenants (≤ 500 in-scope policies)
+**Constraints**:
+- Baseline/monitoring pages must be DB-only at render time (no outbound HTTP)
+- Operation start surfaces enqueue-only (no remote work inline)
+**Scale/Scope**:
+- Multi-tenant, workspace isolation is an authorization boundary
+
+## Constitution Check
+
+*GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.*
+
+- Inventory-first: compare operates on “last observed” inventory/policy versions; baseline snapshot is an explicit immutable capture.
+- Read/write separation: capture/compare are operational jobs; any mutations are confirmed, audited, and tested.
+- Graph contract path: no Graph calls on UI surfaces; any Graph usage (if introduced) must go through `GraphClientInterface` and `config/graph_contracts.php`.
+- Deterministic capabilities: new baseline capabilities are added to the canonical registry and role maps.
+- RBAC-UX semantics: non-member is 404; member but missing capability is 403.
+- Run observability: capture/compare are always `OperationRun`-tracked; start surfaces only create/reuse runs and enqueue work.
+- Data minimization: workspace-owned baseline snapshots are minimized and must not store tenant secrets.
+- Badge semantics (BADGE-001): finding severity/status uses existing `BadgeCatalog` mapping.
+- Filament Action Surface Contract: resources/pages created or modified must define Header/Row/Bulk/Empty-State + inspect affordance.
+
+✅ Phase 0 and Phase 1 design choices satisfy the constitution. No violations are required.
+
+## Project Structure
+
+### Documentation (this feature)
+
+```text
+specs/101-golden-master-baseline-governance-v1/
+├── plan.md
+├── spec.md
+├── research.md
+├── data-model.md
+├── quickstart.md
+└── contracts/
+   └── baseline-governance.openapi.yaml
+```
+
+### Source Code (repository root)
+
+```text
+app/
+├── Filament/
+├── Jobs/
+├── Models/
+├── Policies/
+├── Services/
+└── Support/
+
+database/
+└── migrations/
+
+resources/
+└── views/
+
+tests/
+├── Feature/
+└── Unit/
+```
+
+**Structure Decision**: Implement baseline governance as standard Laravel models, migrations, services, jobs, and Filament resources/pages under the existing `app/` conventions.
+
+## Phase 0 — Research (completed)
+
+Outputs:
+- [research.md](research.md)
+
+Key decisions captured:
+- Workspace-owned, data-minimized baseline snapshots (reusable across tenants)
+- `OperationRun` types `baseline_capture` and `baseline_compare` using `ensureRunWithIdentity()` for idempotent starts
+- Precondition failures return 422 with stable `reason_code` and do not create runs
+- Findings reuse `findings` with sha256 fingerprints; Phase 2 adds `findings.source` to satisfy `source = baseline.compare`
+
+## Phase 1 — Design & Contracts (completed)
+
+Outputs:
+- [data-model.md](data-model.md)
+- [contracts/baseline-governance.openapi.yaml](contracts/baseline-governance.openapi.yaml)
+- [quickstart.md](quickstart.md)
+
+### UI Surfaces (Filament v5)
+
+- Workspace-context: Governance → Baselines
+  - Resource for baseline profile CRUD
+  - Capture action (manage capability)
+  - Tenant assignment management (manage capability)
+- Tenant-context: “Soll vs Ist” landing page
+  - Compare-now action (view capability)
+  - Links to latest compare run + findings
+
+### Authorization & capabilities
+
+- Add new workspace capabilities:
+  - `workspace_baselines.view`
+  - `workspace_baselines.manage`
+- Enforce membership as 404; capability denial as 403.
+
+### Operation types
+
+- `baseline_capture` (tenant = source tenant)
+- `baseline_compare` (tenant = target/current tenant)
+
+### Agent context update (completed)
+
+The agent context update script was run during planning. It should be re-run after this plan update if the automation depends on parsed plan values.
+
+## Phase 2 — Execution Plan (to be translated into tasks.md)
+
+1) **Migrations + models**
+  - Add baseline tables (`baseline_profiles`, `baseline_snapshots`, `baseline_snapshot_items`, `baseline_tenant_assignments`)
+  - Add `findings.source` column + index to meet FR-015
+
+2) **Services**
+  - Baseline scope resolution (profile scope ∩ assignment override)
+  - Snapshot identity calculation and dedupe strategy
+  - Compare engine to produce drift items and severity mapping (FR-009)
+
+3) **Jobs (queued)**
+  - `CaptureBaselineSnapshotJob` (creates snapshot, items, updates active snapshot when applicable)
+  - `CompareBaselineToTenantJob` (creates/updates findings + writes run summary_counts)
+
+4) **Filament UI**
+  - Baseline profiles resource (list/view/edit) with action surfaces per spec matrix
+  - Tenant assignment UI surface (v1: single baseline per tenant)
+  - “Soll vs Ist” tenant landing page and dashboard card action
+
+5) **RBAC + policies**
+  - Capability registry + role maps + UI enforcement
+  - Regression tests for 404 vs 403 semantics
+
+6) **Tests (Pest)**
+  - CRUD authorization + action surface expectations
+  - Capture snapshot dedupe
+  - Compare finding fingerprint idempotency
+  - Precondition failures return 422 and create no `OperationRun`
+
+7) **Formatting**
+  - Run `vendor/bin/sail bin pint --dirty`
+
+## Complexity Tracking
+
+None.
diff --git a/specs/101-golden-master-baseline-governance-v1/quickstart.md b/specs/101-golden-master-baseline-governance-v1/quickstart.md
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+# Phase 1 — Quickstart (Developer)
+
+This quickstart is for exercising Baseline Governance v1 locally.
+
+## Prereqs
+- Docker running
+- Laravel Sail available
+
+## Setup
+1. Start containers: `vendor/bin/sail up -d`
+2. Install deps (if needed): `vendor/bin/sail composer install`
+3. Migrate: `vendor/bin/sail artisan migrate`
+4. Build frontend assets (if UI changes aren’t visible): `vendor/bin/sail npm run dev`
+
+## Happy path walkthrough
+
+### 1) Create a baseline profile
+- Navigate to Admin → Governance → Baselines
+- Create a profile with:
+  - name
+  - status = draft
+  - scope filter (policy types/domains)
+
+### 2) Capture from a source tenant
+- From the Baseline Profile view page, trigger “Capture from tenant”
+- Select a source tenant
+- Confirm the action
+- You should see a queued notification with “View run” that links to Monitoring → Operations
+
+Expected:
+- An `OperationRun` of type `baseline_capture` is created (or reused if one is already queued/running)
+- On success, an immutable `baseline_snapshot` is created and the profile’s `active_snapshot_id` is updated (when profile is active)
+
+### 3) Assign baseline to a tenant
+- Navigate to the tenant context (Admin → choose tenant)
+- Assign the baseline profile to the tenant (v1: exactly one baseline per tenant)
+- Optionally define an override filter that narrows scope
+
+### 4) Compare now (Soll vs Ist)
+- Navigate to the “Soll vs Ist” landing page for the tenant
+- Click “Compare now”
+
+Expected:
+- An `OperationRun` of type `baseline_compare` is created/reused
+- Findings are created/updated with stable fingerprints
+- The compare run summary is persisted (totals + severity breakdown)
+
+## Precondition failure checks
+
+These should return **HTTP 422** with `reason_code`, and must **not** create an `OperationRun`:
+- compare with no assignment: `baseline.compare.no_assignment`
+- compare when profile not active: `baseline.compare.profile_not_active`
+- compare when no active snapshot: `baseline.compare.no_active_snapshot`
+- capture with missing source tenant: `baseline.capture.missing_source_tenant`
+
+## Test focus (when implementation lands)
+- BaselineProfile CRUD + RBAC (404 vs 403)
+- Capture idempotency (dedupe snapshot identity)
+- Compare idempotency (dedupe finding fingerprint)
+- Action surfaces comply with the Filament Action Surface Contract
diff --git a/specs/101-golden-master-baseline-governance-v1/research.md b/specs/101-golden-master-baseline-governance-v1/research.md
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+# Phase 0 — Research
+
+This document records the key technical decisions for **101 — Golden Master / Baseline Governance v1 (R1.1–R1.4)**, grounded in existing TenantPilot patterns.
+
+## Existing System Constraints (confirmed in repo)
+
+### Operation runs are tenant-scoped and deduped at DB level
+- `OperationRunService::ensureRunWithIdentity()` requires a `Tenant` with a non-null `workspace_id`, and always creates runs with `workspace_id` + `tenant_id`.
+- Active-run idempotency is enforced via the `operation_runs_active_unique` partial unique index (queued/running).
+
+**Implication**: Baseline capture/compare must always be executed as **tenant-owned `OperationRun` records**, even though baseline profiles are workspace-owned.
+
+### Findings fingerprinting expects sha256 (64 chars)
+- `findings.fingerprint` is `string(64)` and unique by `(tenant_id, fingerprint)`.
+- `DriftHasher` already implements a stable sha256 fingerprint scheme.
+
+**Implication**: Any baseline-compare “finding key” should be hashed before storage, and must be stable across repeated compares.
+
+## Decisions
+
+### D-001 — Baseline snapshot storage is workspace-owned (and data-minimized)
+**Decision**: Store `baseline_snapshots` and `baseline_snapshot_items` as **workspace-owned** tables (`workspace_id` NOT NULL, **no `tenant_id`**) so a golden master snapshot can be used across tenants without requiring access to the source tenant.
+
+**Rationale**:
+- The product intent is a workspace-level standard (“Golden Master”) reusable across multiple tenants.
+- Treat the snapshot as a **standard artifact**, not tenant evidence, and enforce strict data-minimization so we do not leak tenant-specific content.
+
+**Guardrails**:
+- Snapshot items store only policy identity + stable content hashes and minimal display metadata.
+- Any tenant identifiers (e.g., “captured from tenant”) live in the **capture `OperationRun.context`** and audit logs, not on workspace-owned snapshot rows.
+
+**Alternatives considered**:
+- Tenant-owned baseline snapshot (include `tenant_id`): rejected because it would require cross-tenant reads of tenant-owned records to compare other tenants, which would either violate tenant isolation or force “must be member of the source tenant” semantics.
+
+### D-002 — OperationRun types and identity inputs
+**Decision**:
+- Introduce `OperationRun.type` values:
+  - `baseline_capture`
+  - `baseline_compare`
+- Use `OperationRunService::ensureRunWithIdentity()` for idempotent start surfaces.
+
+**Identity inputs**:
+- `baseline_capture`: identity inputs include `baseline_profile_id`.
+- `baseline_compare`: identity inputs include `baseline_profile_id`.
+
+**Rationale**:
+- Guarantees one active run per tenant+baseline profile (matches partial unique index behavior).
+- Keeps identity stable even if the active snapshot is switched mid-flight; the run context should freeze `baseline_snapshot_id` at enqueue time for determinism.
+
+**Alternatives considered**:
+- Include `baseline_snapshot_id` in identity: rejected for v1 because we primarily want “single active compare per tenant/profile”, not “single active compare per snapshot”.
+
+### D-003 — Precondition failures return 422 and do not create OperationRuns
+**Decision**: Enforce FR-014 exactly:
+- The start surface validates preconditions **before** calling `OperationRunService`.
+- If unmet, return **HTTP 422** with a stable `reason_code` and **do not** create an `OperationRun`.
+
+**Rationale**:
+- Aligns with spec clarifications and avoids polluting Monitoring → Operations with non-startable attempts.
+
+### D-004 — Findings storage uses existing `findings` table; add a source discriminator
+**Decision**:
+- Store baseline-compare drift as `Finding::FINDING_TYPE_DRIFT`.
+- Persist `source = baseline.compare` per FR-015.
+
+**Implementation note**:
+- The current `findings` schema does not have a `source` column.
+- In Phase 2 implementation we should add `findings.source` (string, **nullable**, default `NULL`) with an index `(tenant_id, source)` and use `source='baseline.compare'`.
+- Existing findings receive `NULL` — legacy drift-generate findings are queried with `whereNull('source')` or unconditionally.
+- A future backfill migration may set `source='drift.generate'` for historical findings if needed for reporting.
+
+**Alternatives considered**:
+- Store `source` only in `evidence_jsonb`: workable, but makes filtering and long-term reporting harder and is less explicit.
+- Non-null default `'drift.generate'`: rejected because retroactively tagging all existing findings requires careful validation and is a separate concern.
+
+### D-005 — Baseline compare scope_key strategy
+**Decision**: Use `findings.scope_key = 'baseline_profile:' . baseline_profile_id` for baseline-compare findings.
+
+**Rationale**:
+- Keeps a stable grouping key for tenant UI (“Soll vs Ist” for the assigned baseline).
+- Avoids over-coupling to inventory selection hashes in v1.
+
+### D-006 — Authorization model (404 vs 403)
+**Decision**:
+- Membership is enforced as deny-as-not-found (404) via existing membership checks.
+- Capability denials are 403 after membership is established.
+
+**Capabilities**:
+- Add workspace capabilities:
+  - `workspace_baselines.view`
+  - `workspace_baselines.manage`
+
+**Rationale**:
+- Matches the feature spec’s two-capability requirement.
+- Keeps baseline governance controlled at workspace plane, while still enforcing tenant membership for tenant-context pages/actions.
+
+**Alternatives considered**:
+- Add a tenant-plane capability for compare start: rejected for v1 to keep to the two-capability spec and avoid introducing a second permission axis for the same action.
+
+## Open Questions (none blocking Phase 1)
+- None.
diff --git a/specs/101-golden-master-baseline-governance-v1/spec.md b/specs/101-golden-master-baseline-governance-v1/spec.md
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+# Feature Specification: Golden Master / Baseline Governance v1 (R1.1–R1.4)
+
+**Feature Branch**: `101-golden-master-baseline-governance-v1`  
+**Created**: 2026-02-19  
+**Status**: Draft  
+**Input**: Introduce a workspace-owned “Golden Master” baseline that can be captured from a tenant, compared against the current tenant state, and surfaced in the UI as “Soll vs Ist” with drift findings and an operational summary.
+
+## Spec Scope Fields *(mandatory)*
+
+- **Scope**: workspace
+- **Primary Routes**: Admin Governance “Baselines” area; tenant-facing dashboard card; drift comparison landing (“Soll vs Ist”)
+- **Data Ownership**: Baselines and snapshots are workspace-owned; tenant assignments are tenant-owned (workspace_id + tenant_id); drift findings are tenant-owned (workspace_id + tenant_id)
+- **RBAC**: workspace membership required for any visibility; capability gating for view vs manage (see Requirements)
+
+## Clarifications
+
+### Session 2026-02-19
+
+- Q: Which v1 drift severity mapping should we use? → A: Fixed mapping: missing_policy=high, different_version=medium, unexpected_policy=low.
+- Q: Which snapshot should compare runs use in v1? → A: Always use BaselineProfile.active_snapshot; if missing, block compare with a clear reason.
+- Q: How should compare/capture handle precondition failures? → A: UI disables where possible AND server blocks start with 422 + stable reason_code; no OperationRun is created for failed preconditions.
+- Q: Where should drift findings be stored in v1? → A: Use existing findings storage with source=baseline.compare; fingerprint/idempotency lives there.
+- Q: How should tenant override filters combine with the profile filter? → A: Override narrows scope; effective filter = profile ∩ override.
+
+## User Scenarios & Testing *(mandatory)*
+
+### User Story 1 - Create and manage a baseline profile (Priority: P1)
+
+As a workspace governance owner/manager, I can define what “good” looks like by creating a Baseline Profile, controlling its status (draft/active/archived), and scoping which policy domains are included.
+
+**Why this priority**: Without a baseline profile, there is nothing to capture or compare against.
+
+**Independent Test**: A user with baseline manage rights can create/edit/archive a baseline profile and see it listed; a read-only user can list/view but cannot mutate.
+
+**Acceptance Scenarios**:
+
+1. **Given** I am a workspace member with baseline manage capability, **When** I create a baseline profile with a name, optional description, optional version label, and a policy-domain filter, **Then** the profile is persisted and visible in the Baselines list.
+2. **Given** I am a workspace member with baseline view-only capability, **When** I open a baseline profile, **Then** I can view its details but cannot edit/archive/delete it.
+3. **Given** I am not a member of the workspace, **When** I attempt to access baseline pages, **Then** I receive a not-found response (deny-as-not-found).
+
+---
+
+### User Story 2 - Capture an immutable baseline snapshot from a tenant (Priority: P2)
+
+As a baseline manager, I can capture a snapshot of the current tenant configuration that the baseline profile covers, producing an immutable “baseline snapshot” that can later be compared.
+
+**Why this priority**: The baseline must be based on a real, point-in-time state to be meaningful and auditable.
+
+**Independent Test**: Capturing twice with unchanged tenant state reuses the same snapshot identity and does not create duplicates.
+
+**Acceptance Scenarios**:
+
+1. **Given** a baseline profile exists and I have baseline manage capability, **When** I trigger “Capture from tenant” and choose a source tenant, **Then** a new capture operation is created and eventually produces an immutable snapshot.
+2. **Given** a capture was already completed for the same baseline profile and the tenant’s relevant policies are unchanged, **When** I capture again, **Then** the system reuses the existing snapshot (idempotent/deduped).
+3. **Given** the baseline profile is active, **When** a capture completes successfully, **Then** the profile’s “active snapshot” points to the captured snapshot.
+
+---
+
+### User Story 3 - Compare baseline vs current tenant to detect drift (Priority: P3)
+
+As an operator/manager, I can run “Compare now” for a tenant, and the system produces drift findings and a summary that can be used for assurance and triage.
+
+**Why this priority**: Drift detection is the core governance signal; it makes the baseline actionable.
+
+**Independent Test**: A compare run produces findings for missing policies, different versions, and unexpected policies, and stores a compact summary.
+
+**Acceptance Scenarios**:
+
+1. **Given** a tenant is assigned to an active baseline profile with an active snapshot, **When** I run “Compare now”, **Then** a compare operation runs and produces drift findings and a drift summary.
+2. **Given** the same drift item is detected in repeated compares, **When** compares are run multiple times, **Then** the same finding is updated (idempotent fingerprint) rather than duplicated.
+3. **Given** I am a workspace member without baseline view capability, **When** I try to start a compare, **Then** the request is forbidden.
+
+### Edge Cases
+
+- Baseline profile is draft or archived: compare is blocked; users are told what must be changed (e.g., “activate baseline”).
+- Tenant has no baseline assignment: compare button is disabled and the UI explains why.
+- Baseline profile has no active snapshot yet: compare is blocked with a clear reason.
+- Concurrent operation starts: the system prevents multiple “active” captures/compares for the same scope.
+- Baseline filter yields no relevant policies: capture creates an empty snapshot and compare returns “no items checked”, without errors.
+
+## Requirements *(mandatory)*
+
+### Functional Requirements
+
+- **FR-001 (Baseline Profiles)**: The system MUST allow workspace baseline managers to create, edit, activate, deactivate (return to draft), and archive baseline profiles. Status transitions: draft ↔ active → archived (archived is terminal in v1).
+- **FR-002 (Scope Control)**: Each baseline profile MUST define which policy domains/types are included in the baseline.
+- **FR-003 (Tenant Assignment)**: The system MUST support assigning exactly one baseline profile per tenant per workspace (v1), with an optional per-tenant override of the profile’s scope; in v1 the override may only narrow scope (effective filter = profile ∩ override).
+- **FR-004 (Capture as Operation)**: Capturing a baseline snapshot MUST be tracked as an observable operation with a clear lifecycle (started/completed/failed).
+- **FR-005 (Immutable Snapshots)**: Baseline snapshots and their snapshot items MUST be immutable once created.
+- **FR-006 (Capture Idempotency)**: Captures MUST be deduplicated so that repeated captures with the same effective content reuse the existing snapshot identity.
+- **FR-007 (Compare as Operation)**: Comparing a tenant against its baseline MUST be tracked as an observable operation with a clear lifecycle.
+- **FR-008 (Drift Findings)**: Compare MUST produce drift findings using at least these drift types: missing baseline policy, different version, and unexpected policy within the baseline scope.
+- **FR-009 (Severity Rules)**: Drift findings MUST be assigned severities using centrally defined rules so that severity is consistent and testable; v1 fixed mapping is: missing baseline policy = high, different version = medium, unexpected policy = low.
+- **FR-010 (Finding Idempotency)**: Drift findings MUST be deduplicated with a stable fingerprint so repeated compares update existing open findings instead of creating duplicates.
+- **FR-011 (Summary Output)**: Each compare operation MUST persist a summary containing totals and severity breakdowns suitable for dashboards.
+- **FR-012 (UI “Soll vs Ist”)**: The UI MUST allow selecting a baseline profile and viewing the latest compare runs and drift findings for a tenant.
+- **FR-013 (Compare Snapshot Selection)**: Compare runs MUST always use the baseline profile’s active snapshot; if no active snapshot exists, compare MUST be blocked with a clear reason.
+- **FR-014 (Precondition Failure Contract)**: When capture/compare cannot start due to unmet preconditions, the UI MUST disable the action where possible, and the server MUST reject the request with HTTP 422 containing a stable `reason_code`; in this case, the system MUST NOT create an OperationRun.
+- **FR-015 (Findings Storage)**: Drift findings produced by compare MUST be persisted using the existing findings system with `source = baseline.compare`.
+
+### Precondition `reason_code` (v1)
+
+- `baseline.compare.no_assignment`
+- `baseline.compare.profile_not_active`
+- `baseline.compare.no_active_snapshot`
+- `baseline.capture.missing_source_tenant`
+
+### Constitution Alignment: Safety, Isolation, Observability
+
+- **Ops/Observability**: Capture and compare MUST be observable and auditable operations, and surfaced in the existing operations monitoring experience.
+- **DB-only UI**: Baseline pages and drift pages MUST NOT require outbound network calls during page render or user clicks that only start/view operations; external calls (if any) must happen in background work.
+- **Tenant Isolation / RBAC semantics**:
+  - non-member of workspace or tenant scope → deny-as-not-found (404)
+  - member but missing capability → forbidden (403)
+- **Least privilege**: Two capabilities MUST exist and be enforced:
+  - baseline view: can view baselines and start compare operations
+  - baseline manage: can manage baselines, assignments, and capture snapshots
+- **Auditability**: Baseline-related operations MUST emit audit log entries for started/completed/failed events.
+- **Safe logging**: Failures MUST not include secrets or sensitive tenant data; failure reasons must be stable and suitable for support triage.
+
+## UI Action Matrix *(mandatory when Filament is changed)*
+
+| Surface | Location | Header Actions | Inspect Affordance (List/Table) | Row Actions (max 2 visible) | Bulk Actions (grouped) | Empty-State CTA(s) | View Header Actions | Create/Edit Save+Cancel | Audit log? | Notes / Exemptions |
+|---|---|---|---|---|---|---|---|---|---|---|
+| Baseline Profiles | Admin → Governance → Baselines | Create baseline profile | View/Edit page available | View, Edit | Archive (grouped) | Create baseline profile | Capture from tenant; Activate/Deactivate; Assign to tenants | Save, Cancel | Yes | Destructive actions require confirmation; mutations are manage-gated; hard-delete is out of scope for v1 (archive only) |
+| Drift Landing (“Soll vs Ist”) | Tenant view | Run compare now | Links to last compare operation and findings list | — | — | — | — | — | Yes | Starting compare is view-gated; results visible only to entitled users |
+| Tenant Dashboard Card | Tenant dashboard | Run compare now | Click to drift landing and/or last compare operation | — | — | — | — | — | Yes | Button disabled with explanation when no assignment or no active snapshot |
+
+## Key Entities *(include if feature involves data)*
+
+- **Baseline Profile**: A workspace-owned definition of what should be in-scope for governance, with a lifecycle status (draft/active/archived).
+- **Tenant Assignment**: A workspace-managed mapping that declares which baseline applies to a tenant, optionally overriding scope.
+- **Baseline Snapshot**: An immutable point-in-time record of the baseline’s in-scope policy references captured from a tenant.
+- **Snapshot Item**: A single baseline entry representing one in-scope policy reference in the snapshot.
+- **Drift Finding**: A record representing an observed deviation between baseline and tenant state, deduplicated by a stable fingerprint.
+- **Drift Finding Source**: Drift findings produced by this feature use `source = baseline.compare`.
+- **Operation Summary**: A compact, persisted summary of a capture/compare run suitable for dashboard display.
+
+## Success Criteria *(mandatory)*
+
+### Measurable Outcomes
+
+- **SC-001**: A baseline manager can create a baseline profile and perform an initial capture in under 5 minutes.
+- **SC-002**: For a typical tenant (≤ 500 in-scope policies), a compare run completes and surfaces a summary within 2 minutes.
+- **SC-003**: Re-running compare within 24 hours for unchanged drift does not create duplicate findings (0 duplicate drift fingerprints).
+- **SC-004**: Unauthorized users (non-members) receive no baseline visibility (deny-as-not-found) and members without capability cannot mutate (forbidden).
+
+## Non-Goals (v1)
+
+- Evidence packs / stored reports for audit exports
+- Advanced findings workflow (exceptions, auto-closing, recurrence handling)
+- Cross-tenant portfolio comparisons
+- Baseline inheritance across organizations (e.g., MSP → customer)
+- Assignment/scope-tag baselines beyond the policy domains/types included in the profile scope
+
+## Assumptions
+
+- Tenants already have an inventory of policy versions that can be referenced for capture and compare.
+- An operations monitoring experience exists where capture/compare runs can be viewed.
+- A drift findings system exists that can store and display findings and severities.
+
+## Dependencies
+
+- Inventory + policy version history is available and trustworthy.
+- Operation run tracking and monitoring is available.
+- RBAC + UI enforcement semantics are already established (404 for non-member, 403 for missing capability).
+- Alerts are optional for v1; the feature remains valuable without alert integrations.
diff --git a/specs/101-golden-master-baseline-governance-v1/tasks.md b/specs/101-golden-master-baseline-governance-v1/tasks.md
new file mode 100644
index 0000000..9647c63
--- /dev/null
+++ b/specs/101-golden-master-baseline-governance-v1/tasks.md
@@ -0,0 +1,209 @@
+---
+
+description: "Task breakdown for implementing Feature 101"
+---
+
+# Tasks: Golden Master / Baseline Governance v1
+
+**Input**: Design documents from `specs/101-golden-master-baseline-governance-v1/`
+
+**Key constraints (from spec/plan)**
+- Filament v5 + Livewire v4.0+ only.
+- UI surfaces are DB-only at render time (no outbound HTTP).
+- Capture/compare start surfaces are enqueue-only (no remote work inline).
+- Precondition failures return **HTTP 422** with stable `reason_code` and **must not** create an `OperationRun`.
+- RBAC semantics: non-member → **404** (deny-as-not-found); member but missing capability → **403**.
+- Findings use sha256 64-char fingerprints (reuse `App\Services\Drift\DriftHasher`).
+
+---
+
+## Phase 1: Setup (Shared Infrastructure)
+
+**Purpose**: Ensure the repo is ready for implementation + verification.
+
+- [X] T001 Verify feature docs are in place in specs/101-golden-master-baseline-governance-v1/
+- [X] T002 Verify local dev prerequisites via quickstart in specs/101-golden-master-baseline-governance-v1/quickstart.md
+
+---
+
+## Phase 2: Foundational (Blocking Prerequisites)
+
+**Purpose**: Core primitives used across all user stories (schema, capabilities, operation UX).
+
+**Checkpoint**: After this phase, US1/US2/US3 work can proceed.
+
+- [X] T003 Add baseline capabilities to app/Support/Auth/Capabilities.php (`workspace_baselines.view`, `workspace_baselines.manage`)
+- [X] T004 Add baseline capabilities to app/Services/Auth/WorkspaceRoleCapabilityMap.php (Owner/Manager = manage; Operator/Readonly = view)
+- [X] T005 [P] Add operation labels for baseline_capture + baseline_compare in app/Support/OperationCatalog.php
+- [X] T006 [P] Extend summary keys to include severity breakdown keys in app/Support/OpsUx/OperationSummaryKeys.php (add `high`, `medium`, `low`)
+- [X] T007 Create baseline schema migrations in database/migrations/*_create_baseline_profiles_table.php (workspace-owned)
+- [X] T008 Create baseline schema migrations in database/migrations/*_create_baseline_snapshots_table.php (workspace-owned)
+- [X] T009 Create baseline schema migrations in database/migrations/*_create_baseline_snapshot_items_table.php (workspace-owned)
+- [X] T010 Create baseline schema migrations in database/migrations/*_create_baseline_tenant_assignments_table.php (tenant-owned)
+- [X] T011 Create findings source migration in database/migrations/*_add_source_to_findings_table.php
+- [X] T012 [P] Add BaselineProfile model in app/Models/BaselineProfile.php (casts for scope_jsonb; status constants/enum)
+- [X] T013 [P] Add BaselineSnapshot model in app/Models/BaselineSnapshot.php (casts for summary_jsonb)
+- [X] T014 [P] Add BaselineSnapshotItem model in app/Models/BaselineSnapshotItem.php (casts for meta_jsonb)
+- [X] T015 [P] Add BaselineTenantAssignment model in app/Models/BaselineTenantAssignment.php (casts for override_scope_jsonb)
+- [X] T016 [P] Update Finding model for new column in app/Models/Finding.php (fillable/casts for `source` as needed by existing conventions)
+- [X] T017 [P] Add baseline scope value object / helpers in app/Support/Baselines/BaselineScope.php (normalize + intersect profile/override)
+- [X] T018 [P] Add baseline reason codes in app/Support/Baselines/BaselineReasonCodes.php (constants for 422 responses)
+- [X] T018a [P] Add BadgeDomain::BaselineProfileStatus case to app/Support/Badges/BadgeDomain.php + create domain mapper class in app/Support/Badges/Domains/BaselineProfileStatusBadges.php + register in BadgeCatalog (BADGE-001 compliance for draft/active/archived)
+- [X] T018b [P] Add model factories: database/factories/BaselineProfileFactory.php, BaselineSnapshotFactory.php, BaselineSnapshotItemFactory.php, BaselineTenantAssignmentFactory.php (required for Pest tests in Phase 3–5)
+
+---
+
+## Phase 3: User Story 1 — Baseline Profile CRUD (Priority: P1) 🎯 MVP
+
+**Goal**: Workspace managers define baseline profiles (scope + lifecycle) with correct RBAC and action surfaces.
+
+**Independent Test**: 
+- As a member with `workspace_baselines.manage`, create/edit/archive a profile.
+- As a member with `workspace_baselines.view`, list/view but cannot mutate.
+- As a non-member, baseline pages/actions deny-as-not-found (404).
+
+### Tests (required in this repo)
+
+- [X] T019 [P] [US1] Add feature test scaffolding in tests/Feature/Baselines/BaselineProfileAuthorizationTest.php
+- [X] T020 [P] [US1] Add 404 vs 403 semantics tests in tests/Feature/Baselines/BaselineProfileAuthorizationTest.php
+- [X] T021 [P] [US1] Add Action Surface contract coverage for the new resource in tests/Feature/Guards/ActionSurfaceValidatorTest.php (resource discovered or explicitly whitelisted per existing test conventions)
+
+### Implementation
+
+- [X] T022 [US1] Create Baseline Profile Filament resource in app/Filament/Resources/BaselineProfileResource.php (navigation group = Governance)
+- [X] T023 [P] [US1] Add resource pages in app/Filament/Resources/BaselineProfileResource/Pages/ListBaselineProfiles.php
+- [X] T024 [P] [US1] Add resource pages in app/Filament/Resources/BaselineProfileResource/Pages/CreateBaselineProfile.php
+- [X] T025 [P] [US1] Add resource pages in app/Filament/Resources/BaselineProfileResource/Pages/ViewBaselineProfile.php
+- [X] T026 [P] [US1] Add resource pages in app/Filament/Resources/BaselineProfileResource/Pages/EditBaselineProfile.php
+- [X] T027 [US1] Implement form/table schema in app/Filament/Resources/BaselineProfileResource.php (scope editor backed by App\Support\Inventory\InventoryPolicyTypeMeta)
+- [X] T028 [US1] Implement RBAC (404 vs 403) and UI enforcement in app/Filament/Resources/BaselineProfileResource.php using App\Services\Auth\WorkspaceCapabilityResolver + App\Support\Rbac\WorkspaceUiEnforcement
+- [X] T029 [US1] Implement audit logging for baseline profile mutations in app/Filament/Resources/BaselineProfileResource.php using App\Services\Audit\WorkspaceAuditLogger
+- [X] T030 [US1] Ensure the resource is safe for global search (either keep View/Edit pages enabled OR disable global search explicitly) in app/Filament/Resources/BaselineProfileResource.php
+
+**Checkpoint**: Baseline profiles CRUD works and is independently testable.
+
+---
+
+## Phase 4: User Story 2 — Capture Immutable Baseline Snapshot (Priority: P2)
+
+**Goal**: Managers can enqueue capture from a tenant to create (or reuse) an immutable, workspace-owned snapshot.
+
+**Independent Test**:
+- Trigger capture twice for unchanged effective content → the same `snapshot_identity_hash` is reused (no duplicates).
+- If profile is active, capture success updates `active_snapshot_id`.
+
+### Tests (required in this repo)
+
+- [X] T031 [P] [US2] Add capture enqueue + precondition tests in tests/Feature/Baselines/BaselineCaptureTest.php (include: empty-scope capture produces empty snapshot without errors [EC-005])
+- [X] T032 [P] [US2] Add snapshot dedupe test in tests/Feature/Baselines/BaselineCaptureTest.php (include: concurrent capture request for same scope reuses active run [EC-004])
+
+### Implementation
+
+- [X] T033 [P] [US2] Add capture action UI to app/Filament/Resources/BaselineProfileResource/Pages/ViewBaselineProfile.php (Action::make()->action()->requiresConfirmation(); select source tenant; gated by `workspace_baselines.manage` via WorkspaceUiEnforcement — disabled with tooltip for view-only members, server-side 403 on execution)
+- [X] T034 [US2] Add capture start service in app/Services/Baselines/BaselineCaptureService.php (precondition validation before OperationRun creation; enqueue via OperationRunService)
+- [X] T035 [P] [US2] Add snapshot identity helper in app/Services/Baselines/BaselineSnapshotIdentity.php (sha256 over normalized items; reuse DriftHasher::hashNormalized where appropriate)
+- [X] T036 [P] [US2] Add capture job in app/Jobs/CaptureBaselineSnapshotJob.php (DB-only reads; creates snapshot + items; updates profile active snapshot when applicable)
+- [X] T037 [US2] Add audit logging for capture started/completed/failed in app/Jobs/CaptureBaselineSnapshotJob.php using App\Services\Intune\AuditLogger
+- [X] T038 [US2] Persist run context + summary_counts for capture in app/Jobs/CaptureBaselineSnapshotJob.php (use only allowed summary keys)
+
+**Checkpoint**: Capture creates immutable snapshots and dedupes repeated capture.
+
+---
+
+## Phase 5: User Story 3 — Assign + Compare (“Soll vs Ist”) (Priority: P3)
+
+**Goal**: Operators can assign a baseline to a tenant (v1: exactly one), then enqueue compare-now to generate drift findings + summary.
+
+**Independent Test**:
+- With assignment + active snapshot: compare enqueues an operation and produces findings + summary.
+- Re-running compare updates existing findings (same fingerprint) rather than duplicating.
+
+### Tests (required in this repo)
+
+- [X] T039 [P] [US3] Add assignment CRUD tests (RBAC + uniqueness) in tests/Feature/Baselines/BaselineAssignmentTest.php
+- [X] T040 [P] [US3] Add compare precondition 422 tests (no OperationRun created) in tests/Feature/Baselines/BaselineComparePreconditionsTest.php (include: concurrent compare reuses active run [EC-004]; draft/archived profile blocks compare [EC-001])
+- [X] T041 [P] [US3] Add compare idempotent finding fingerprint tests in tests/Feature/Baselines/BaselineCompareFindingsTest.php
+- [X] T042 [P] [US3] Add compare summary_counts severity breakdown tests in tests/Feature/Baselines/BaselineCompareFindingsTest.php
+
+### Implementation — Assignment (v1)
+
+- [X] T043 [P] [US3] Add BaselineTenantAssignments relation manager in app/Filament/Resources/BaselineProfileResource/RelationManagers/BaselineTenantAssignmentsRelationManager.php
+- [X] T044 [US3] Enforce assignment RBAC (404 vs 403) and audits in app/Filament/Resources/BaselineProfileResource/RelationManagers/BaselineTenantAssignmentsRelationManager.php (manage-gated mutations; view-gated visibility)
+- [X] T045 [US3] Implement effective scope validation (override narrows only) in app/Services/Baselines/BaselineScope.php
+
+### Implementation — Tenant landing + dashboard card
+
+- [X] T046 [P] [US3] Add tenant landing page in app/Filament/Pages/BaselineCompareLanding.php (navigation label “Soll vs Ist”; DB-only)
+- [X] T047 [P] [US3] Add landing view in resources/views/filament/pages/baseline-compare-landing.blade.php (shows assignment state, last run link, findings link)
+- [X] T048 [P] [US3] Add tenant dashboard card widget in app/Filament/Widgets/Dashboard/BaselineCompareNow.php
+- [X] T049 [US3] Wire the widget into app/Filament/Pages/TenantDashboard.php (add widget class to getWidgets())
+
+### Implementation — Compare engine + job
+
+- [X] T050 [US3] Add compare start service in app/Services/Baselines/BaselineCompareService.php (preconditions; enqueue OperationRun; freeze snapshot_id in run context)
+- [X] T051 [P] [US3] Add compare job in app/Jobs/CompareBaselineToTenantJob.php (DB-only; compute drift items; upsert findings with `source='baseline.compare'`)
+- [X] T052 [US3] Implement fingerprinting + idempotent upsert in app/Jobs/CompareBaselineToTenantJob.php (use App\Services\Drift\DriftHasher::fingerprint)
+- [X] T053 [US3] Implement severity mapping (missing=high, different=medium, unexpected=low) in app/Jobs/CompareBaselineToTenantJob.php
+- [X] T054 [US3] Persist run summary_counts with totals + severity breakdown in app/Jobs/CompareBaselineToTenantJob.php (requires T006)
+- [X] T055 [US3] Add audit logging for compare started/completed/failed in app/Jobs/CompareBaselineToTenantJob.php using App\Services\Intune\AuditLogger
+
+**Checkpoint**: Tenant “Soll vs Ist” UI works end-to-end and compare generates deduped findings.
+
+---
+
+## Phase 6: Polish & Cross-Cutting Concerns
+
+- [X] T056 [P] Add operation duration hinting for new operation types in app/Support/OperationCatalog.php (expectedDurationSeconds for baseline_capture/baseline_compare)
+- [X] T057 Ensure all destructive actions have confirmation in app/Filament/Resources/BaselineProfileResource.php and app/Filament/Resources/BaselineProfileResource/RelationManagers/BaselineTenantAssignmentsRelationManager.php
+- [X] T058 Run formatting on touched files via `vendor/bin/sail bin pint --dirty`
+- [X] T059 Run focused test suite via `vendor/bin/sail artisan test --compact tests/Feature/Baselines`
+- [X] T060 Run the quickstart walkthrough in specs/101-golden-master-baseline-governance-v1/quickstart.md and adjust any mismatches; spot-check SC-001 (create+capture < 5 min) and SC-002 (compare < 2 min for ≤ 500 policies)
+
+---
+
+## Dependencies & Execution Order
+
+### Phase Dependencies
+
+- Phase 1 (Setup) → Phase 2 (Foundational) → US phases
+- Phase 2 blocks US1/US2/US3.
+
+### User Story Dependencies
+
+- **US1 (P1)** is the MVP and enables profile CRUD.
+- **US2 (P2)** depends on US1 (needs profiles) and Phase 2 schema/services.
+- **US3 (P3)** depends on US1 (needs profiles) and Phase 2 schema; compare also depends on US2 having produced an active snapshot.
+
+---
+
+## Parallel Execution Examples
+
+### US1 parallelizable work
+
+- T023, T024, T025, T026 (resource pages) can be implemented in parallel.
+- T019 and T020 (authorization tests) can be implemented in parallel with the resource skeleton.
+
+### US2 parallelizable work
+
+- T035 (snapshot identity helper) and T036 (capture job) can be implemented in parallel once the schema exists.
+- T031–T032 tests can be written before the job/service implementation.
+
+### US3 parallelizable work
+
+- T046–T048 (landing page + view + widget) can be done in parallel with T050–T054 (compare service/job).
+- T039–T042 tests can be written before implementation.
+
+---
+
+## Implementation Strategy
+
+### MVP First (US1 only)
+
+1. Complete Phase 1 + Phase 2
+2. Deliver Phase 3 (US1)
+3. Run: `vendor/bin/sail artisan test --compact tests/Feature/Baselines/BaselineProfileAuthorizationTest.php`
+
+### Incremental delivery
+
+- Add US2 (capture) → validate dedupe + active snapshot updates
+- Add US3 (assign + compare) → validate 422 contract + idempotent findings + summary output
diff --git a/tests/Feature/Baselines/BaselineAssignmentTest.php b/tests/Feature/Baselines/BaselineAssignmentTest.php
new file mode 100644
index 0000000..64df738
--- /dev/null
+++ b/tests/Feature/Baselines/BaselineAssignmentTest.php
@@ -0,0 +1,126 @@
+<?php
+
+use App\Models\BaselineProfile;
+use App\Models\BaselineTenantAssignment;
+use App\Models\Tenant;
+use App\Models\User;
+use App\Services\Audit\WorkspaceAuditLogger;
+
+// --- T039: Assignment CRUD tests (RBAC + uniqueness) ---
+
+it('creates a tenant assignment with workspace context', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $assignment = BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+        'assigned_by_user_id' => (int) $user->getKey(),
+    ]);
+
+    expect($assignment)->toBeInstanceOf(BaselineTenantAssignment::class);
+    expect($assignment->workspace_id)->toBe((int) $tenant->workspace_id);
+    expect($assignment->tenant_id)->toBe((int) $tenant->getKey());
+    expect($assignment->baseline_profile_id)->toBe((int) $profile->getKey());
+    expect($assignment->assigned_by_user_id)->toBe((int) $user->getKey());
+});
+
+it('prevents duplicate assignments for the same workspace+tenant', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile1 = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+    $profile2 = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile1->getKey(),
+        'assigned_by_user_id' => (int) $user->getKey(),
+    ]);
+
+    // Attempting to assign the same tenant in the same workspace should fail
+    // due to the unique constraint on (workspace_id, tenant_id)
+    expect(fn () => BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile2->getKey(),
+        'assigned_by_user_id' => (int) $user->getKey(),
+    ]))->toThrow(\Illuminate\Database\QueryException::class);
+});
+
+it('allows the same tenant to be assigned in different workspaces', function () {
+    [$user1, $tenant1] = createUserWithTenant(role: 'owner');
+    [$user2, $tenant2] = createUserWithTenant(role: 'owner');
+
+    $profile1 = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant1->workspace_id,
+    ]);
+    $profile2 = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant2->workspace_id,
+    ]);
+
+    $a1 = BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant1->workspace_id,
+        'tenant_id' => (int) $tenant1->getKey(),
+        'baseline_profile_id' => (int) $profile1->getKey(),
+    ]);
+    $a2 = BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant2->workspace_id,
+        'tenant_id' => (int) $tenant2->getKey(),
+        'baseline_profile_id' => (int) $profile2->getKey(),
+    ]);
+
+    expect($a1->exists)->toBeTrue();
+    expect($a2->exists)->toBeTrue();
+});
+
+it('deletes an assignment without deleting related models', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+
+    $assignment = BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+        'assigned_by_user_id' => (int) $user->getKey(),
+    ]);
+
+    $assignmentId = $assignment->getKey();
+    $assignment->delete();
+
+    expect(BaselineTenantAssignment::query()->find($assignmentId))->toBeNull();
+    expect(BaselineProfile::query()->find($profile->getKey()))->not->toBeNull();
+    expect(Tenant::query()->find($tenant->getKey()))->not->toBeNull();
+});
+
+it('loads the baseline profile relationship from assignment', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'name' => 'Test Profile',
+    ]);
+
+    $assignment = BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $loaded = $assignment->baselineProfile;
+
+    expect($loaded)->not->toBeNull();
+    expect($loaded->name)->toBe('Test Profile');
+});
diff --git a/tests/Feature/Baselines/BaselineCaptureTest.php b/tests/Feature/Baselines/BaselineCaptureTest.php
new file mode 100644
index 0000000..b9f69fc
--- /dev/null
+++ b/tests/Feature/Baselines/BaselineCaptureTest.php
@@ -0,0 +1,349 @@
+<?php
+
+use App\Jobs\CaptureBaselineSnapshotJob;
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshot;
+use App\Models\BaselineSnapshotItem;
+use App\Models\InventoryItem;
+use App\Models\OperationRun;
+use App\Services\Baselines\BaselineCaptureService;
+use App\Services\Baselines\BaselineSnapshotIdentity;
+use App\Services\Intune\AuditLogger;
+use App\Services\OperationRunService;
+use Illuminate\Support\Facades\Queue;
+
+// --- T031: Capture enqueue + precondition tests ---
+
+it('enqueues capture for an active profile and creates an operation run', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    /** @var BaselineCaptureService $service */
+    $service = app(BaselineCaptureService::class);
+    $result = $service->startCapture($profile, $tenant, $user);
+
+    expect($result['ok'])->toBeTrue();
+    expect($result)->toHaveKey('run');
+
+    /** @var OperationRun $run */
+    $run = $result['run'];
+    expect($run->type)->toBe('baseline_capture');
+    expect($run->status)->toBe('queued');
+    expect($run->tenant_id)->toBe((int) $tenant->getKey());
+
+    $context = is_array($run->context) ? $run->context : [];
+    expect($context['baseline_profile_id'])->toBe((int) $profile->getKey());
+    expect($context['source_tenant_id'])->toBe((int) $tenant->getKey());
+
+    Queue::assertPushed(CaptureBaselineSnapshotJob::class);
+});
+
+it('rejects capture for a draft profile with reason code', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'status' => BaselineProfile::STATUS_DRAFT,
+    ]);
+
+    $service = app(BaselineCaptureService::class);
+    $result = $service->startCapture($profile, $tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe('baseline.capture.profile_not_active');
+
+    Queue::assertNotPushed(CaptureBaselineSnapshotJob::class);
+    expect(OperationRun::query()->where('type', 'baseline_capture')->count())->toBe(0);
+});
+
+it('rejects capture for an archived profile with reason code', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->archived()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+
+    $service = app(BaselineCaptureService::class);
+    $result = $service->startCapture($profile, $tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe('baseline.capture.profile_not_active');
+
+    Queue::assertNotPushed(CaptureBaselineSnapshotJob::class);
+    expect(OperationRun::query()->where('type', 'baseline_capture')->count())->toBe(0);
+});
+
+it('rejects capture for a tenant from a different workspace', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+    [$otherUser, $otherTenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+
+    $service = app(BaselineCaptureService::class);
+    $result = $service->startCapture($profile, $otherTenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe('baseline.capture.missing_source_tenant');
+
+    Queue::assertNotPushed(CaptureBaselineSnapshotJob::class);
+});
+
+// --- T032: Concurrent capture reuses active run [EC-004] ---
+
+it('reuses an existing active run for the same profile/tenant instead of creating a new one', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $service = app(BaselineCaptureService::class);
+
+    $result1 = $service->startCapture($profile, $tenant, $user);
+    $result2 = $service->startCapture($profile, $tenant, $user);
+
+    expect($result1['ok'])->toBeTrue();
+    expect($result2['ok'])->toBeTrue();
+
+    expect($result1['run']->getKey())->toBe($result2['run']->getKey());
+    expect(OperationRun::query()->where('type', 'baseline_capture')->count())->toBe(1);
+});
+
+// --- Snapshot dedupe + capture job execution ---
+
+it('creates a snapshot with items when the capture job executes', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    InventoryItem::factory()->count(3)->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => ['odata_type' => '#microsoft.graph.deviceConfiguration'],
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_capture',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'source_tenant_id' => (int) $tenant->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CaptureBaselineSnapshotJob($run);
+    $job->handle(
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    expect($run->status)->toBe('completed');
+    expect($run->outcome)->toBe('succeeded');
+
+    $counts = is_array($run->summary_counts) ? $run->summary_counts : [];
+    expect((int) ($counts['total'] ?? 0))->toBe(3);
+    expect((int) ($counts['succeeded'] ?? 0))->toBe(3);
+
+    $snapshot = BaselineSnapshot::query()
+        ->where('baseline_profile_id', $profile->getKey())
+        ->first();
+
+    expect($snapshot)->not->toBeNull();
+    expect(BaselineSnapshotItem::query()->where('baseline_snapshot_id', $snapshot->getKey())->count())->toBe(3);
+
+    $profile->refresh();
+    expect($profile->active_snapshot_id)->toBe((int) $snapshot->getKey());
+});
+
+it('dedupes snapshots when content is unchanged', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    InventoryItem::factory()->count(2)->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => ['odata_type' => '#microsoft.graph.deviceConfiguration', 'stable_field' => 'value'],
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $idService = app(BaselineSnapshotIdentity::class);
+    $auditLogger = app(AuditLogger::class);
+
+    $run1 = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_capture',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'source_tenant_id' => (int) $tenant->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job1 = new CaptureBaselineSnapshotJob($run1);
+    $job1->handle($idService, $auditLogger, $opService);
+
+    $snapshotCountAfterFirst = BaselineSnapshot::query()
+        ->where('baseline_profile_id', $profile->getKey())
+        ->count();
+
+    expect($snapshotCountAfterFirst)->toBe(1);
+
+    $run2 = OperationRun::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'user_id' => (int) $user->getKey(),
+        'initiator_name' => $user->name,
+        'type' => 'baseline_capture',
+        'status' => 'queued',
+        'outcome' => 'pending',
+        'run_identity_hash' => hash('sha256', 'second-run-' . now()->timestamp),
+        'context' => [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'source_tenant_id' => (int) $tenant->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+    ]);
+
+    $job2 = new CaptureBaselineSnapshotJob($run2);
+    $job2->handle($idService, $auditLogger, $opService);
+
+    $snapshotCountAfterSecond = BaselineSnapshot::query()
+        ->where('baseline_profile_id', $profile->getKey())
+        ->count();
+
+    expect($snapshotCountAfterSecond)->toBe(1);
+});
+
+// --- EC-005: Empty scope produces empty snapshot without errors ---
+
+it('captures an empty snapshot when no inventory items match the scope', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['nonExistentPolicyType']],
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_capture',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'source_tenant_id' => (int) $tenant->getKey(),
+            'effective_scope' => ['policy_types' => ['nonExistentPolicyType']],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CaptureBaselineSnapshotJob($run);
+    $job->handle(
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    expect($run->status)->toBe('completed');
+    expect($run->outcome)->toBe('succeeded');
+
+    $counts = is_array($run->summary_counts) ? $run->summary_counts : [];
+    expect((int) ($counts['total'] ?? 0))->toBe(0);
+    expect((int) ($counts['failed'] ?? 0))->toBe(0);
+
+    $snapshot = BaselineSnapshot::query()
+        ->where('baseline_profile_id', $profile->getKey())
+        ->first();
+
+    expect($snapshot)->not->toBeNull();
+    expect(BaselineSnapshotItem::query()->where('baseline_snapshot_id', $snapshot->getKey())->count())->toBe(0);
+});
+
+it('captures all inventory items when scope has empty policy_types (all types)', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => []],
+    ]);
+
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'policy_type' => 'deviceConfiguration',
+    ]);
+
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'policy_type' => 'compliancePolicy',
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_capture',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'source_tenant_id' => (int) $tenant->getKey(),
+            'effective_scope' => ['policy_types' => []],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CaptureBaselineSnapshotJob($run);
+    $job->handle(
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    expect($run->status)->toBe('completed');
+
+    $counts = is_array($run->summary_counts) ? $run->summary_counts : [];
+    expect((int) ($counts['total'] ?? 0))->toBe(2);
+
+    $snapshot = BaselineSnapshot::query()
+        ->where('baseline_profile_id', $profile->getKey())
+        ->first();
+
+    expect($snapshot)->not->toBeNull();
+    expect(BaselineSnapshotItem::query()->where('baseline_snapshot_id', $snapshot->getKey())->count())->toBe(2);
+});
diff --git a/tests/Feature/Baselines/BaselineCompareFindingsTest.php b/tests/Feature/Baselines/BaselineCompareFindingsTest.php
new file mode 100644
index 0000000..bbf8704
--- /dev/null
+++ b/tests/Feature/Baselines/BaselineCompareFindingsTest.php
@@ -0,0 +1,414 @@
+<?php
+
+use App\Jobs\CompareBaselineToTenantJob;
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshot;
+use App\Models\BaselineSnapshotItem;
+use App\Models\BaselineTenantAssignment;
+use App\Models\Finding;
+use App\Models\InventoryItem;
+use App\Models\OperationRun;
+use App\Services\Baselines\BaselineSnapshotIdentity;
+use App\Services\Drift\DriftHasher;
+use App\Services\Intune\AuditLogger;
+use App\Services\OperationRunService;
+
+// --- T041: Compare idempotent finding fingerprint tests ---
+
+it('creates drift findings when baseline and tenant inventory differ', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    // Baseline has policyA and policyB
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'policy-a-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => hash('sha256', 'content-a'),
+        'meta_jsonb' => ['display_name' => 'Policy A'],
+    ]);
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'policy-b-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => hash('sha256', 'content-b'),
+        'meta_jsonb' => ['display_name' => 'Policy B'],
+    ]);
+
+    // Tenant has policyA (different content) and policyC (unexpected)
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'external_id' => 'policy-a-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => ['different_content' => true],
+        'display_name' => 'Policy A modified',
+    ]);
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'external_id' => 'policy-c-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => ['new_policy' => true],
+        'display_name' => 'Policy C unexpected',
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_compare',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CompareBaselineToTenantJob($run);
+    $job->handle(
+        app(DriftHasher::class),
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    expect($run->status)->toBe('completed');
+    expect($run->outcome)->toBe('succeeded');
+
+    $scopeKey = 'baseline_profile:' . $profile->getKey();
+
+    $findings = Finding::query()
+        ->where('tenant_id', $tenant->getKey())
+        ->where('source', 'baseline.compare')
+        ->where('scope_key', $scopeKey)
+        ->get();
+
+    // policyB missing (high), policyA different (medium), policyC unexpected (low) = 3 findings
+    expect($findings->count())->toBe(3);
+
+    $severities = $findings->pluck('severity')->sort()->values()->all();
+    expect($severities)->toContain(Finding::SEVERITY_HIGH);
+    expect($severities)->toContain(Finding::SEVERITY_MEDIUM);
+    expect($severities)->toContain(Finding::SEVERITY_LOW);
+});
+
+it('produces idempotent fingerprints so re-running compare updates existing findings', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'policy-x-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => hash('sha256', 'baseline-content'),
+        'meta_jsonb' => ['display_name' => 'Policy X'],
+    ]);
+
+    // Tenant does NOT have policy-x → missing_policy finding
+    $opService = app(OperationRunService::class);
+
+    // First run
+    $run1 = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_compare',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job1 = new CompareBaselineToTenantJob($run1);
+    $job1->handle(
+        app(DriftHasher::class),
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $scopeKey = 'baseline_profile:' . $profile->getKey();
+    $countAfterFirst = Finding::query()
+        ->where('tenant_id', $tenant->getKey())
+        ->where('source', 'baseline.compare')
+        ->where('scope_key', $scopeKey)
+        ->count();
+
+    expect($countAfterFirst)->toBe(1);
+
+    // Second run - new OperationRun so we can dispatch again
+    // Mark first run as completed so ensureRunWithIdentity creates a new one
+    $run1->update(['status' => 'completed', 'completed_at' => now()]);
+
+    $run2 = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_compare',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job2 = new CompareBaselineToTenantJob($run2);
+    $job2->handle(
+        app(DriftHasher::class),
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $countAfterSecond = Finding::query()
+        ->where('tenant_id', $tenant->getKey())
+        ->where('source', 'baseline.compare')
+        ->where('scope_key', $scopeKey)
+        ->count();
+
+    // Same fingerprint → same finding updated, not duplicated
+    expect($countAfterSecond)->toBe(1);
+});
+
+it('creates zero findings when baseline matches tenant inventory exactly', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    // Baseline item
+    $metaContent = ['policy_key' => 'value123'];
+    $driftHasher = app(DriftHasher::class);
+    $contentHash = $driftHasher->hashNormalized($metaContent);
+
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'matching-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => $contentHash,
+        'meta_jsonb' => ['display_name' => 'Matching Policy'],
+    ]);
+
+    // Tenant inventory with same content → same hash
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'external_id' => 'matching-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => $metaContent,
+        'display_name' => 'Matching Policy',
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_compare',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CompareBaselineToTenantJob($run);
+    $job->handle(
+        app(DriftHasher::class),
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    expect($run->status)->toBe('completed');
+    expect($run->outcome)->toBe('succeeded');
+
+    $counts = is_array($run->summary_counts) ? $run->summary_counts : [];
+    expect((int) ($counts['total'] ?? -1))->toBe(0);
+
+    $findings = Finding::query()
+        ->where('tenant_id', $tenant->getKey())
+        ->where('source', 'baseline.compare')
+        ->count();
+
+    expect($findings)->toBe(0);
+});
+
+// --- T042: Summary counts severity breakdown tests ---
+
+it('writes severity breakdown in summary_counts', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    // 2 baseline items: one will be missing (high), one will be different (medium)
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'missing-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => hash('sha256', 'missing-content'),
+        'meta_jsonb' => ['display_name' => 'Missing Policy'],
+    ]);
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'changed-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => hash('sha256', 'original-content'),
+        'meta_jsonb' => ['display_name' => 'Changed Policy'],
+    ]);
+
+    // Tenant only has changed-uuid with different content + extra-uuid (unexpected)
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'external_id' => 'changed-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => ['modified_content' => true],
+        'display_name' => 'Changed Policy',
+    ]);
+    InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'workspace_id' => $tenant->workspace_id,
+        'external_id' => 'extra-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'meta_jsonb' => ['extra_content' => true],
+        'display_name' => 'Extra Policy',
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_compare',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CompareBaselineToTenantJob($run);
+    $job->handle(
+        app(DriftHasher::class),
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    $counts = is_array($run->summary_counts) ? $run->summary_counts : [];
+
+    expect((int) ($counts['total'] ?? -1))->toBe(3);
+    expect((int) ($counts['high'] ?? -1))->toBe(1);   // missing-uuid
+    expect((int) ($counts['medium'] ?? -1))->toBe(1);  // changed-uuid
+    expect((int) ($counts['low'] ?? -1))->toBe(1);     // extra-uuid
+});
+
+it('writes result context with findings breakdown', function () {
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    // One missing policy
+    BaselineSnapshotItem::factory()->create([
+        'baseline_snapshot_id' => $snapshot->getKey(),
+        'subject_type' => 'policy',
+        'subject_external_id' => 'gone-uuid',
+        'policy_type' => 'deviceConfiguration',
+        'baseline_hash' => hash('sha256', 'gone-content'),
+    ]);
+
+    $opService = app(OperationRunService::class);
+    $run = $opService->ensureRunWithIdentity(
+        tenant: $tenant,
+        type: 'baseline_compare',
+        identityInputs: ['baseline_profile_id' => (int) $profile->getKey()],
+        context: [
+            'baseline_profile_id' => (int) $profile->getKey(),
+            'baseline_snapshot_id' => (int) $snapshot->getKey(),
+            'effective_scope' => ['policy_types' => ['deviceConfiguration']],
+        ],
+        initiator: $user,
+    );
+
+    $job = new CompareBaselineToTenantJob($run);
+    $job->handle(
+        app(DriftHasher::class),
+        app(BaselineSnapshotIdentity::class),
+        app(AuditLogger::class),
+        $opService,
+    );
+
+    $run->refresh();
+    $context = is_array($run->context) ? $run->context : [];
+    $result = $context['result'] ?? [];
+
+    expect($result)->toHaveKey('findings_total');
+    expect($result)->toHaveKey('findings_upserted');
+    expect($result)->toHaveKey('severity_breakdown');
+    expect((int) $result['findings_total'])->toBe(1);
+    expect((int) $result['findings_upserted'])->toBe(1);
+});
diff --git a/tests/Feature/Baselines/BaselineComparePreconditionsTest.php b/tests/Feature/Baselines/BaselineComparePreconditionsTest.php
new file mode 100644
index 0000000..b8df465
--- /dev/null
+++ b/tests/Feature/Baselines/BaselineComparePreconditionsTest.php
@@ -0,0 +1,178 @@
+<?php
+
+use App\Jobs\CompareBaselineToTenantJob;
+use App\Models\BaselineProfile;
+use App\Models\BaselineSnapshot;
+use App\Models\BaselineTenantAssignment;
+use App\Models\OperationRun;
+use App\Services\Baselines\BaselineCompareService;
+use App\Support\Baselines\BaselineReasonCodes;
+use Illuminate\Support\Facades\Queue;
+
+// --- T040: Compare precondition 422 tests ---
+
+it('rejects compare when tenant has no baseline assignment', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_NO_ASSIGNMENT);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(0);
+});
+
+it('rejects compare when assigned profile is in draft status', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'status' => BaselineProfile::STATUS_DRAFT,
+    ]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+    expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(0);
+});
+
+it('rejects compare when assigned profile is archived [EC-001]', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->archived()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_PROFILE_NOT_ACTIVE);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+});
+
+it('rejects compare when profile has no active snapshot', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'active_snapshot_id' => null,
+    ]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeFalse();
+    expect($result['reason_code'])->toBe(BaselineReasonCodes::COMPARE_NO_ACTIVE_SNAPSHOT);
+
+    Queue::assertNotPushed(CompareBaselineToTenantJob::class);
+});
+
+it('enqueues compare successfully when all preconditions are met', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'scope_jsonb' => ['policy_types' => ['deviceConfiguration']],
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+    $result = $service->startCompare($tenant, $user);
+
+    expect($result['ok'])->toBeTrue();
+    expect($result)->toHaveKey('run');
+
+    /** @var OperationRun $run */
+    $run = $result['run'];
+    expect($run->type)->toBe('baseline_compare');
+    expect($run->status)->toBe('queued');
+
+    $context = is_array($run->context) ? $run->context : [];
+    expect($context['baseline_profile_id'])->toBe((int) $profile->getKey());
+    expect($context['baseline_snapshot_id'])->toBe((int) $snapshot->getKey());
+
+    Queue::assertPushed(CompareBaselineToTenantJob::class);
+});
+
+// --- EC-004: Concurrent compare reuses active run ---
+
+it('reuses an existing active run for the same profile/tenant instead of creating a new one [EC-004]', function () {
+    Queue::fake();
+
+    [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+    $profile = BaselineProfile::factory()->active()->create([
+        'workspace_id' => $tenant->workspace_id,
+    ]);
+
+    $snapshot = BaselineSnapshot::factory()->create([
+        'workspace_id' => $tenant->workspace_id,
+        'baseline_profile_id' => $profile->getKey(),
+    ]);
+
+    $profile->update(['active_snapshot_id' => $snapshot->getKey()]);
+
+    BaselineTenantAssignment::create([
+        'workspace_id' => (int) $tenant->workspace_id,
+        'tenant_id' => (int) $tenant->getKey(),
+        'baseline_profile_id' => (int) $profile->getKey(),
+    ]);
+
+    $service = app(BaselineCompareService::class);
+
+    $result1 = $service->startCompare($tenant, $user);
+    $result2 = $service->startCompare($tenant, $user);
+
+    expect($result1['ok'])->toBeTrue();
+    expect($result2['ok'])->toBeTrue();
+    expect($result1['run']->getKey())->toBe($result2['run']->getKey());
+    expect(OperationRun::query()->where('type', 'baseline_compare')->count())->toBe(1);
+});
diff --git a/tests/Feature/Baselines/BaselineProfileAuthorizationTest.php b/tests/Feature/Baselines/BaselineProfileAuthorizationTest.php
new file mode 100644
index 0000000..5817486
--- /dev/null
+++ b/tests/Feature/Baselines/BaselineProfileAuthorizationTest.php
@@ -0,0 +1,156 @@
+<?php
+
+declare(strict_types=1);
+
+use App\Filament\Resources\BaselineProfileResource;
+use App\Models\BaselineProfile;
+use App\Models\User;
+use App\Models\Workspace;
+use App\Models\WorkspaceMembership;
+use App\Services\Auth\WorkspaceCapabilityResolver;
+use App\Support\Workspaces\WorkspaceContext;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+
+uses(RefreshDatabase::class);
+
+describe('BaselineProfile RBAC — 404 vs 403 semantics', function () {
+    it('denies non-members accessing the list page', function (): void {
+        $user = User::factory()->create();
+        $workspace = Workspace::factory()->create();
+
+        session()->put(WorkspaceContext::SESSION_KEY, (int) $workspace->getKey());
+
+        $response = $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl(panel: 'admin'));
+
+        expect($response->status())->toBeIn([403, 404, 302], 'Non-members should not get HTTP 200');
+    });
+
+    it('returns 404 for members accessing a profile from another workspace', function (): void {
+        [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+        $otherWorkspace = Workspace::factory()->create();
+        $profile = BaselineProfile::factory()->create([
+            'workspace_id' => (int) $otherWorkspace->getKey(),
+        ]);
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl('view', ['record' => $profile], panel: 'admin'))
+            ->assertNotFound();
+    });
+
+    it('returns 200 for readonly members accessing list page', function (): void {
+        [$user] = createUserWithTenant(role: 'readonly');
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl(panel: 'admin'))
+            ->assertOk();
+    });
+
+    it('returns 403 for members with mocked missing capability on list page', function (): void {
+        $workspace = Workspace::factory()->create();
+        $user = User::factory()->create();
+
+        WorkspaceMembership::factory()->create([
+            'workspace_id' => (int) $workspace->getKey(),
+            'user_id' => (int) $user->getKey(),
+            'role' => 'readonly',
+        ]);
+
+        $resolver = \Mockery::mock(WorkspaceCapabilityResolver::class);
+        $resolver->shouldReceive('isMember')->andReturnTrue();
+        $resolver->shouldReceive('can')->andReturnFalse();
+        app()->instance(WorkspaceCapabilityResolver::class, $resolver);
+
+        session()->put(WorkspaceContext::SESSION_KEY, (int) $workspace->getKey());
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl(panel: 'admin'))
+            ->assertForbidden();
+    });
+
+    it('returns 403 for readonly members accessing create page', function (): void {
+        [$user] = createUserWithTenant(role: 'readonly');
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl('create', panel: 'admin'))
+            ->assertForbidden();
+    });
+
+    it('returns 200 for owner members accessing create page', function (): void {
+        [$user] = createUserWithTenant(role: 'owner');
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl('create', panel: 'admin'))
+            ->assertOk();
+    });
+
+    it('returns 404 for members accessing profile from another workspace', function (): void {
+        [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+        $otherWorkspace = Workspace::factory()->create();
+        $profile = BaselineProfile::factory()->create([
+            'workspace_id' => (int) $otherWorkspace->getKey(),
+        ]);
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl('view', ['record' => $profile], panel: 'admin'))
+            ->assertNotFound();
+    });
+
+    it('returns 403 for readonly members accessing edit page', function (): void {
+        [$user, $tenant] = createUserWithTenant(role: 'readonly');
+
+        $workspace = Workspace::query()->whereKey($tenant->workspace_id)->first();
+        $profile = BaselineProfile::factory()->create([
+            'workspace_id' => (int) $workspace->getKey(),
+        ]);
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl('edit', ['record' => $profile], panel: 'admin'))
+            ->assertForbidden();
+    });
+
+    it('returns 200 for owner members accessing edit page', function (): void {
+        [$user, $tenant] = createUserWithTenant(role: 'owner');
+
+        $workspace = Workspace::query()->whereKey($tenant->workspace_id)->first();
+        $profile = BaselineProfile::factory()->create([
+            'workspace_id' => (int) $workspace->getKey(),
+        ]);
+
+        $this->actingAs($user)
+            ->get(BaselineProfileResource::getUrl('edit', ['record' => $profile], panel: 'admin'))
+            ->assertOk();
+    });
+});
+
+describe('BaselineProfile static authorization methods', function () {
+    it('canViewAny returns false for non-members', function (): void {
+        $user = User::factory()->create();
+        $workspace = Workspace::factory()->create();
+
+        $this->actingAs($user);
+        session()->put(WorkspaceContext::SESSION_KEY, (int) $workspace->getKey());
+
+        expect(BaselineProfileResource::canViewAny())->toBeFalse();
+    });
+
+    it('canViewAny returns true for members', function (): void {
+        [$user] = createUserWithTenant(role: 'readonly');
+
+        $this->actingAs($user);
+
+        expect(BaselineProfileResource::canViewAny())->toBeTrue();
+    });
+
+    it('canCreate returns true for managers and false for readonly', function (): void {
+        [$owner] = createUserWithTenant(role: 'owner');
+        $this->actingAs($owner);
+        expect(BaselineProfileResource::canCreate())->toBeTrue();
+
+        [$readonly] = createUserWithTenant(role: 'readonly');
+        $this->actingAs($readonly);
+        expect(BaselineProfileResource::canCreate())->toBeFalse();
+    });
+});
diff --git a/tests/Feature/Guards/ActionSurfaceContractTest.php b/tests/Feature/Guards/ActionSurfaceContractTest.php
index 5039e17..8189b42 100644
--- a/tests/Feature/Guards/ActionSurfaceContractTest.php
+++ b/tests/Feature/Guards/ActionSurfaceContractTest.php
@@ -2,6 +2,7 @@
 
 declare(strict_types=1);
 
+use App\Filament\Resources\BaselineProfileResource;
 use App\Filament\Resources\InventoryItemResource;
 use App\Filament\Resources\InventoryItemResource\Pages\ListInventoryItems;
 use App\Filament\Resources\OperationRunResource;
@@ -73,6 +74,24 @@
     }
 });
 
+it('discovers the baseline profile resource and validates its declaration', function (): void {
+    $components = collect(ActionSurfaceValidator::withBaselineExemptions()->discoveredComponents())
+        ->keyBy('className');
+
+    $baselineResource = $components->get(BaselineProfileResource::class);
+
+    expect($baselineResource)->not->toBeNull('BaselineProfileResource should be discovered by action surface discovery');
+    expect($baselineResource?->hasPanelScope(ActionSurfacePanelScope::Admin))->toBeTrue();
+
+    $declaration = BaselineProfileResource::actionSurfaceDeclaration();
+    $profiles = new ActionSurfaceProfileDefinition;
+
+    foreach ($profiles->requiredSlots($declaration->profile) as $slot) {
+        expect($declaration->slot($slot))
+            ->not->toBeNull("Missing required slot {$slot->value} in BaselineProfileResource declaration");
+    }
+});
+
 it('ensures representative declarations satisfy required slots', function (): void {
     $profiles = new ActionSurfaceProfileDefinition;
 
@@ -80,6 +99,7 @@
         PolicyResource::class => PolicyResource::actionSurfaceDeclaration(),
         OperationRunResource::class => OperationRunResource::actionSurfaceDeclaration(),
         VersionsRelationManager::class => VersionsRelationManager::actionSurfaceDeclaration(),
+        BaselineProfileResource::class => BaselineProfileResource::actionSurfaceDeclaration(),
     ];
 
     foreach ($declarations as $className => $declaration) {