Merge feat/data-layer-contracts into main (Stage 8B complete)

docs/development/build_execution_tracker.md

@@ -2,9 +2,9 @@
 
 ## Current status
 
-- main baseline updated through: integrations-contracts (Stage 8A complete)
-- next branch: feat/data-layer-contracts (Stage 8B)
-- current stage: Stage 8A complete — integration abstractions activated
+- main baseline updated through: data-layer-contracts (Stage 8B complete)
+- next branch: feat/auth-foundation (Stage 8C)
+- current stage: Stage 8B complete — shared data layer abstractions activated
 
 ## Slice tracker
 
@@ -402,6 +402,25 @@
 - analyze: passed (dart analyze --fatal-infos — no issues found in integrations and feature_wordpress)
 - brief updated: yes
 
+### feat/data-layer-contracts
+
+- status: merged to main
+- date: 2026-07-11
+- inspection: complete
+- implementation: complete
+- files changed:
+  - `data/lib/src/local_cache.dart` — new `LocalCache<T>` abstract contract; `InMemoryCache<T>` implementation with TTL-based expiry, key enumeration, and dispose
+  - `data/lib/src/sync_queue.dart` — new `SyncOperationStatus` enum, `SyncOperation` value object with `copyWith()`; `SyncFlushResult` with `success`/`failure` constructors; `SyncQueue` abstract contract; `InMemorySyncQueue` implementation with enqueue, process (success/failure tracking), remove, pruneCompleted, and length
+  - `data/lib/src/conflict_resolver.dart` — new `ConflictResolution` enum, `ConflictResult<T>` with `useLocal`/`useRemote`/`merged`/`requiresReview` constructors; `ConflictResolver<T>` abstract contract; `LastWriteWinsResolver<T>`, `LocalAlwaysWinsResolver<T>`, `RemoteAlwaysWinsResolver<T>` concrete implementations
+  - `data/lib/src/change_tracker.dart` — new `ChangeState` enum, `TrackedChange<T>` value object with `copyWith()`; `ChangeTracker<T>` abstract contract; `InMemoryChangeTracker<T>` implementation with trackCreated/trackModified/trackDeleted/markSynced/markSyncError/pendingChanges/hasPendingChanges/clear
+  - `data/lib/src/data_mapper.dart` — new `DataMapper<TLocal, TRemote>` abstract contract with `fromRemote`/`toRemote`/`fromRemoteList`/`toRemoteList`; `DataMappingException` with field, message, rawValue
+  - `data/lib/data.dart` — replaced `Calculator` placeholder with barrel exports for all 5 new contract files
+  - `data/test/data_test.dart` — replaced placeholder test with 63 tests covering all contracts and implementations
+  - `kell_creations_apps/tools/run_all_tests.sh` — added `packages/data` to both `TESTABLE` and `ANALYZABLE` lists
+- tests: passed (63/63 data)
+- analyze: passed (dart analyze --fatal-infos — no issues found)
+- brief updated: yes
+
 ### feat/bulk-operator-workflows
 
 - status: merged to main

docs/development/master_development_brief.md

@@ -70,8 +70,8 @@ Rules:
   - `feature_policy` — domain, application, data (fake), and presentation layers
 - Scaffolded but **empty stub** packages (created, no implementation yet):
   - `auth` — authentication/authorization (stub only)
-  - `data` — shared data layer (stub only)
   - `integrations` — ✅ integration contracts activated (Stage 8A complete); `ApiClient`, `ApiException`, `RetryPolicy`, `RateLimiter`, `IntegrationHealthCheck`, `WebhookHandler`, `ChannelAdapter` contracts defined; `WooCommerceApiClient` and `WooCommerceApiException` refactored to implement shared contracts
+  - `data` — ✅ shared data layer contracts activated (Stage 8B complete); `LocalCache<T>`, `SyncQueue`, `ConflictResolver<T>`, `ChangeTracker<T>`, `DataMapper<TLocal, TRemote>` contracts defined with in-memory implementations
   - `feature_finance` — financial analysis feature (stub only)
   - `feature_mrp` — craft manufacturing/MRP feature (stub only)
   - `feature_social` — social media management feature (stub only)
@@ -123,6 +123,7 @@ Rules:
 - ✅ Inventory mobile surface landed (Stage 6C complete — merged `feat/inventory-mobile-surface` → `main`, 2026-07-10). Stage 6 complete.
 - ✅ Bulk publish and bulk submit-for-review actions landed (Stage 7B complete — merged `feat/bulk-operator-workflows` → `main`, 2026-07-11). Stage 7 complete.
 - ✅ Integration abstractions activated (Stage 8A complete — merged `feat/integrations-contracts` → `main`, 2026-07-11).
+- ✅ Shared data layer contracts activated (Stage 8B complete — merged `feat/data-layer-contracts` → `main`, 2026-07-11).
 
 ### Current narrow edit capabilities on `main`
 
@@ -147,9 +148,10 @@ Rules:
 - latest reported count for `feature_wordpress`: `319/319 passed`
 - latest reported count for `kell_web`: `24/24 passed`
 - latest reported count for `integrations`: `38/38 passed`
+- latest reported count for `data`: `63/63 passed`
 - latest reported count for `kell_mobile`: `26/26 passed`
-- total: `658/658 passed`
-- baseline commit: merge of `feat/integrations-contracts` into `main` (Stage 8A complete, 2026-07-11)
+- total: `721/721 passed`
+- baseline commit: merge of `feat/data-layer-contracts` into `main` (Stage 8B complete, 2026-07-11)
 
 #### Baseline test coverage (established 2026-05-22)
 
@@ -165,8 +167,8 @@ No minimum thresholds are enforced — this is visibility-only tracking. Coverag
 
 ### Next recommended branch
 
-**`feat/data-layer-contracts`** — Stage 8B: Shared data layer abstractions.
-Branch from latest `main`. Stage 8A (integration abstractions) is complete. Stage 8B provides shared data abstractions for local caching, offline storage, and cross-feature data patterns required by Stages 9–16.
+**`feat/auth-foundation`** — Stage 8C: Authentication foundation.
+Branch from latest `main`. Stages 8A (integration abstractions) and 8B (data layer contracts) are complete. Stage 8C provides the `AuthService` contract, `CredentialStore`, `User`/`AuthState` domain models, and `SecureCredentialStore` implementation required before multi-user or production deployment.
 
 ---
 

kell_creations_apps/packages/data/lib/data.dart

@@ -1,5 +1,13 @@
-/// A Calculator.
-class Calculator {
-  /// Returns [value] plus 1.
-  int addOne(int value) => value + 1;
-}
+/// Shared data layer abstractions for the Kell Creations platform.
+///
+/// This library defines the contracts for local caching, offline operation
+/// queuing, multi-channel conflict resolution, change tracking, and
+/// local ↔ remote model mapping. Concrete implementations (SQLite-backed,
+/// in-memory, etc.) are provided alongside each contract.
+library;
+
+export 'src/change_tracker.dart';
+export 'src/conflict_resolver.dart';
+export 'src/data_mapper.dart';
+export 'src/local_cache.dart';
+export 'src/sync_queue.dart';

kell_creations_apps/packages/data/lib/src/change_tracker.dart

@@ -0,0 +1,165 @@
+/// The sync state of a locally-tracked record.
+enum ChangeState {
+  /// The record matches the last known remote state — no action needed.
+  synced,
+
+  /// The record was created locally and has not yet been pushed to the remote.
+  created,
+
+  /// The record was modified locally since the last successful sync.
+  modified,
+
+  /// The record was deleted locally and the deletion has not yet been applied
+  /// on the remote.
+  deleted,
+
+  /// A sync attempt failed; the record needs to be retried.
+  syncError,
+}
+
+/// Tracks the local modification state of a single record pending sync.
+class TrackedChange<T> {
+  /// Identifier of the record being tracked (matches the domain entity's id).
+  final String id;
+
+  /// The current local state of the record, or `null` if [state] is
+  /// [ChangeState.deleted].
+  final T? value;
+
+  /// The sync state of this record.
+  final ChangeState state;
+
+  /// When this change was first recorded locally.
+  final DateTime changedAt;
+
+  /// Error message from the last failed sync attempt, if any.
+  final String? syncError;
+
+  const TrackedChange({
+    required this.id,
+    required this.state,
+    required this.changedAt,
+    this.value,
+    this.syncError,
+  });
+
+  /// Returns a copy with the given fields replaced.
+  TrackedChange<T> copyWith({T? value, ChangeState? state, String? syncError}) {
+    return TrackedChange<T>(
+      id: id,
+      value: value ?? this.value,
+      state: state ?? this.state,
+      changedAt: changedAt,
+      syncError: syncError ?? this.syncError,
+    );
+  }
+
+  @override
+  String toString() => 'TrackedChange(id: $id, state: $state, changedAt: $changedAt)';
+}
+
+/// Tracks local modifications to domain records that are pending synchronisation
+/// with a remote channel.
+///
+/// [T] is the domain type being tracked (e.g. `InventoryItem`, `Order`).
+///
+/// Implementations record which records have been created, modified, or deleted
+/// locally so that a sync engine can determine exactly what needs to be pushed
+/// to the remote on the next sync pass.
+abstract class ChangeTracker<T> {
+  /// Records that [record] with [id] was created locally.
+  Future<void> trackCreated(String id, T record);
+
+  /// Records that [record] with [id] was modified locally.
+  Future<void> trackModified(String id, T record);
+
+  /// Records that the record with [id] was deleted locally.
+  Future<void> trackDeleted(String id);
+
+  /// Marks the record with [id] as successfully synced (removes it from the
+  /// pending-changes set).
+  Future<void> markSynced(String id);
+
+  /// Records a sync error for [id] with the given [errorMessage].
+  Future<void> markSyncError(String id, String errorMessage);
+
+  /// Returns all records that have pending local changes (created, modified,
+  /// deleted, or errored).
+  Future<List<TrackedChange<T>>> pendingChanges();
+
+  /// Returns the [TrackedChange] for [id], or `null` if the record is synced
+  /// or not tracked.
+  Future<TrackedChange<T>?> getChange(String id);
+
+  /// Returns `true` if there are any pending local changes.
+  Future<bool> get hasPendingChanges;
+
+  /// Clears all tracked changes (e.g. after a full re-sync from the remote).
+  Future<void> clear();
+}
+
+/// An in-memory [ChangeTracker] suitable for testing and development.
+class InMemoryChangeTracker<T> implements ChangeTracker<T> {
+  final Map<String, TrackedChange<T>> _changes = {};
+
+  @override
+  Future<void> trackCreated(String id, T record) async {
+    _changes[id] = TrackedChange<T>(
+      id: id,
+      value: record,
+      state: ChangeState.created,
+      changedAt: DateTime.now(),
+    );
+  }
+
+  @override
+  Future<void> trackModified(String id, T record) async {
+    // Preserve the original changedAt if already tracked as created.
+    final existing = _changes[id];
+    _changes[id] = TrackedChange<T>(
+      id: id,
+      value: record,
+      state: existing?.state == ChangeState.created ? ChangeState.created : ChangeState.modified,
+      changedAt: existing?.changedAt ?? DateTime.now(),
+    );
+  }
+
+  @override
+  Future<void> trackDeleted(String id) async {
+    final existing = _changes[id];
+    _changes[id] = TrackedChange<T>(
+      id: id,
+      value: null,
+      state: ChangeState.deleted,
+      changedAt: existing?.changedAt ?? DateTime.now(),
+    );
+  }
+
+  @override
+  Future<void> markSynced(String id) async {
+    _changes.remove(id);
+  }
+
+  @override
+  Future<void> markSyncError(String id, String errorMessage) async {
+    final existing = _changes[id];
+    if (existing != null) {
+      _changes[id] = existing.copyWith(state: ChangeState.syncError, syncError: errorMessage);
+    }
+  }
+
+  @override
+  Future<List<TrackedChange<T>>> pendingChanges() async {
+    return _changes.values.where((c) => c.state != ChangeState.synced).toList()
+      ..sort((a, b) => a.changedAt.compareTo(b.changedAt));
+  }
+
+  @override
+  Future<TrackedChange<T>?> getChange(String id) async => _changes[id];
+
+  @override
+  Future<bool> get hasPendingChanges async => _changes.isNotEmpty;
+
+  @override
+  Future<void> clear() async => _changes.clear();
+}

kell_creations_apps/packages/data/lib/src/conflict_resolver.dart

@@ -0,0 +1,136 @@
+/// The outcome of a conflict resolution decision.
+enum ConflictResolution {
+  /// Use the local version of the record.
+  useLocal,
+
+  /// Use the remote version of the record.
+  useRemote,
+
+  /// Merge both versions into a new record (implementation-defined).
+  merge,
+
+  /// Escalate to the operator — neither version is automatically chosen.
+  requiresOperatorReview,
+}
+
+/// The result produced by a [ConflictResolver] for a single conflicting record.
+class ConflictResult<T> {
+  /// Which version was chosen (or how the conflict was handled).
+  final ConflictResolution resolution;
+
+  /// The resolved record, or `null` when [resolution] is
+  /// [ConflictResolution.requiresOperatorReview].
+  final T? resolvedValue;
+
+  /// Human-readable explanation of why this resolution was chosen.
+  final String? reason;
+
+  const ConflictResult({required this.resolution, this.resolvedValue, this.reason});
+
+  /// Convenience constructor: local version wins.
+  const ConflictResult.useLocal({required T local, this.reason})
+    : resolution = ConflictResolution.useLocal,
+      resolvedValue = local;
+
+  /// Convenience constructor: remote version wins.
+  const ConflictResult.useRemote({required T remote, this.reason})
+    : resolution = ConflictResolution.useRemote,
+      resolvedValue = remote;
+
+  /// Convenience constructor: merged value produced.
+  const ConflictResult.merged({required T merged, this.reason})
+    : resolution = ConflictResolution.merge,
+      resolvedValue = merged;
+
+  /// Convenience constructor: operator review required.
+  const ConflictResult.requiresReview({this.reason})
+    : resolution = ConflictResolution.requiresOperatorReview,
+      resolvedValue = null;
+
+  @override
+  String toString() => 'ConflictResult(resolution: $resolution, reason: $reason)';
+}
+
+/// Contract for resolving conflicts between a locally-modified record and a
+/// remotely-modified record of the same entity.
+///
+/// [T] is the domain type being reconciled (e.g. `InventoryItem`, `Order`).
+///
+/// Implementations encode the business rules for which version wins when both
+/// the local app and a remote channel (WooCommerce, Square) have modified the
+/// same record since the last sync.
+abstract class ConflictResolver<T> {
+  /// Resolves the conflict between [local] and [remote] versions of a record.
+  ///
+  /// [localModifiedAt] and [remoteModifiedAt] are the last-modified timestamps
+  /// for each version, used by time-based strategies.
+  ConflictResult<T> resolve({
+    required T local,
+    required T remote,
+    required DateTime localModifiedAt,
+    required DateTime remoteModifiedAt,
+  });
+}
+
+/// A [ConflictResolver] that always prefers the most recently modified version.
+///
+/// When timestamps are equal the remote version is preferred, on the assumption
+/// that the remote is the authoritative source of truth.
+class LastWriteWinsResolver<T> implements ConflictResolver<T> {
+  const LastWriteWinsResolver();
+
+  @override
+  ConflictResult<T> resolve({
+    required T local,
+    required T remote,
+    required DateTime localModifiedAt,
+    required DateTime remoteModifiedAt,
+  }) {
+    if (localModifiedAt.isAfter(remoteModifiedAt)) {
+      return ConflictResult.useLocal(
+        local: local,
+        reason: 'Local version is newer (last-write-wins)',
+      );
+    }
+    return ConflictResult.useRemote(
+      remote: remote,
+      reason: 'Remote version is newer or equal (last-write-wins)',
+    );
+  }
+}
+
+/// A [ConflictResolver] that always prefers the local version.
+///
+/// Useful when the app is the authoritative source of truth and remote changes
+/// should never overwrite local edits.
+class LocalAlwaysWinsResolver<T> implements ConflictResolver<T> {
+  const LocalAlwaysWinsResolver();
+
+  @override
+  ConflictResult<T> resolve({
+    required T local,
+    required T remote,
+    required DateTime localModifiedAt,
+    required DateTime remoteModifiedAt,
+  }) {
+    return ConflictResult.useLocal(local: local, reason: 'Local always wins policy');
+  }
+}
+
+/// A [ConflictResolver] that always prefers the remote version.
+///
+/// Useful when the remote channel is the authoritative source of truth and
+/// local edits should be discarded on conflict.
+class RemoteAlwaysWinsResolver<T> implements ConflictResolver<T> {
+  const RemoteAlwaysWinsResolver();
+
+  @override
+  ConflictResult<T> resolve({
+    required T local,
+    required T remote,
+    required DateTime localModifiedAt,
+    required DateTime remoteModifiedAt,
+  }) {
+    return ConflictResult.useRemote(remote: remote, reason: 'Remote always wins policy');
+  }
+}

kell_creations_apps/packages/data/lib/src/data_mapper.dart

@@ -0,0 +1,53 @@
+/// Contract for bidirectional mapping between a local domain model and a
+/// remote data transfer object (DTO).
+///
+/// [TLocal] is the domain type used inside the app (e.g. `InventoryItem`).
+/// [TRemote] is the wire/DTO type returned by the remote API
+/// (e.g. a `Map<String, dynamic>` decoded from JSON, or a typed DTO class).
+///
+/// Implementations live in the data layer of each feature package and keep
+/// all serialisation/deserialisation logic out of the domain layer.
+abstract class DataMapper<TLocal, TRemote> {
+  /// Converts a [remote] DTO into a local domain object.
+  ///
+  /// Throws a [DataMappingException] if [remote] is missing required fields
+  /// or contains values that cannot be mapped to the domain model.
+  TLocal fromRemote(TRemote remote);
+
+  /// Converts a [local] domain object into a remote DTO suitable for sending
+  /// to the API (e.g. as a JSON request body).
+  TRemote toRemote(TLocal local);
+
+  /// Converts a list of [remote] DTOs into a list of local domain objects.
+  ///
+  /// Delegates to [fromRemote] for each element. Implementations may override
+  /// this for batch-optimised mapping.
+  List<TLocal> fromRemoteList(List<TRemote> remotes) => remotes.map(fromRemote).toList();
+
+  /// Converts a list of [local] domain objects into a list of remote DTOs.
+  ///
+  /// Delegates to [toRemote] for each element. Implementations may override
+  /// this for batch-optimised mapping.
+  List<TRemote> toRemoteList(List<TLocal> locals) => locals.map(toRemote).toList();
+}
+
+/// Thrown when a [DataMapper] cannot convert a remote DTO to a local model.
+///
+/// Carries the [field] that caused the problem and a human-readable [message].
+class DataMappingException implements Exception {
+  /// The field or path within the remote DTO that caused the mapping failure.
+  final String field;
+
+  /// Human-readable description of the mapping failure.
+  final String message;
+
+  /// The raw value that could not be mapped, if available.
+  final Object? rawValue;
+
+  const DataMappingException({required this.field, required this.message, this.rawValue});
+
+  @override
+  String toString() =>
+      'DataMappingException(field: $field): $message'
+      '${rawValue != null ? ' (raw: $rawValue)' : ''}';
+}

kell_creations_apps/packages/data/lib/src/local_cache.dart

@@ -0,0 +1,96 @@
+/// Contract for in-memory and persistent local caching.
+///
+/// [T] is the type of value stored in the cache. Implementations may back
+/// this with an in-memory map, SQLite, shared preferences, or any other
+/// storage mechanism appropriate for the platform.
+abstract class LocalCache<T> {
+  /// Returns the cached value for [key], or `null` if the key is absent or
+  /// the entry has expired.
+  Future<T?> get(String key);
+
+  /// Stores [value] under [key].
+  ///
+  /// If [ttl] is provided the entry expires after that duration and subsequent
+  /// [get] calls will return `null`.
+  Future<void> put(String key, T value, {Duration? ttl});
+
+  /// Removes the entry for [key]. No-op if the key is not present.
+  Future<void> remove(String key);
+
+  /// Removes all entries from the cache.
+  Future<void> clear();
+
+  /// Returns `true` if [key] is present and has not expired.
+  Future<bool> containsKey(String key);
+
+  /// Returns all non-expired keys currently in the cache.
+  Future<List<String>> keys();
+
+  /// Releases any resources held by this cache (file handles, DB connections).
+  Future<void> dispose();
+}
+
+/// A [LocalCache] backed by an in-memory [Map].
+///
+/// Entries are lost when the process exits. Suitable for short-lived caching
+/// within a single app session (e.g. caching API responses for the duration
+/// of a screen visit).
+class InMemoryCache<T> implements LocalCache<T> {
+  final Map<String, _CacheEntry<T>> _store = {};
+
+  @override
+  Future<T?> get(String key) async {
+    final entry = _store[key];
+    if (entry == null) return null;
+    if (entry.isExpired) {
+      _store.remove(key);
+      return null;
+    }
+    return entry.value;
+  }
+
+  @override
+  Future<void> put(String key, T value, {Duration? ttl}) async {
+    _store[key] = _CacheEntry(
+      value: value,
+      expiresAt: ttl != null ? DateTime.now().add(ttl) : null,
+    );
+  }
+
+  @override
+  Future<void> remove(String key) async => _store.remove(key);
+
+  @override
+  Future<void> clear() async => _store.clear();
+
+  @override
+  Future<bool> containsKey(String key) async {
+    final entry = _store[key];
+    if (entry == null) return false;
+    if (entry.isExpired) {
+      _store.remove(key);
+      return false;
+    }
+    return true;
+  }
+
+  @override
+  Future<List<String>> keys() async {
+    // Prune expired entries before returning keys.
+    _store.removeWhere((_, entry) => entry.isExpired);
+    return _store.keys.toList();
+  }
+
+  @override
+  Future<void> dispose() async => _store.clear();
+}
+
+/// Internal entry wrapper that tracks an optional expiry time.
+class _CacheEntry<T> {
+  final T value;
+  final DateTime? expiresAt;
+
+  const _CacheEntry({required this.value, this.expiresAt});
+
+  bool get isExpired => expiresAt != null && DateTime.now().isAfter(expiresAt!);
+}

kell_creations_apps/packages/data/lib/src/sync_queue.dart

@@ -0,0 +1,188 @@
+/// The processing status of a [SyncOperation].
+enum SyncOperationStatus {
+  /// Waiting to be sent to the remote.
+  pending,
+
+  /// Currently being transmitted.
+  inProgress,
+
+  /// Successfully applied on the remote.
+  completed,
+
+  /// Failed after all retry attempts; requires operator attention.
+  failed,
+}
+
+/// A single unit of work that must be applied to a remote system.
+///
+/// Operations are created locally (e.g. while offline) and flushed to the
+/// remote when connectivity is restored.
+class SyncOperation {
+  /// Unique identifier for this operation.
+  final String id;
+
+  /// Logical type of the operation (e.g. `'createOrder'`, `'adjustInventory'`).
+  final String type;
+
+  /// Serialisable payload describing the operation.
+  final Map<String, dynamic> payload;
+
+  /// When this operation was enqueued.
+  final DateTime enqueuedAt;
+
+  /// Current processing status.
+  final SyncOperationStatus status;
+
+  /// Number of times this operation has been attempted.
+  final int attemptCount;
+
+  /// Human-readable error from the last failed attempt, if any.
+  final String? lastError;
+
+  const SyncOperation({
+    required this.id,
+    required this.type,
+    required this.payload,
+    required this.enqueuedAt,
+    this.status = SyncOperationStatus.pending,
+    this.attemptCount = 0,
+    this.lastError,
+  });
+
+  /// Returns a copy of this operation with the given fields replaced.
+  SyncOperation copyWith({SyncOperationStatus? status, int? attemptCount, String? lastError}) {
+    return SyncOperation(
+      id: id,
+      type: type,
+      payload: payload,
+      enqueuedAt: enqueuedAt,
+      status: status ?? this.status,
+      attemptCount: attemptCount ?? this.attemptCount,
+      lastError: lastError ?? this.lastError,
+    );
+  }
+
+  @override
+  String toString() =>
+      'SyncOperation(id: $id, type: $type, status: $status, attempts: $attemptCount)';
+}
+
+/// Result returned after attempting to flush a [SyncOperation].
+class SyncFlushResult {
+  /// The operation that was attempted.
+  final SyncOperation operation;
+
+  /// Whether the flush succeeded.
+  final bool success;
+
+  /// Error message if [success] is `false`.
+  final String? errorMessage;
+
+  const SyncFlushResult({required this.operation, required this.success, this.errorMessage});
+
+  const SyncFlushResult.success({required this.operation}) : success = true, errorMessage = null;
+
+  const SyncFlushResult.failure({required this.operation, required this.errorMessage})
+    : success = false;
+
+  @override
+  String toString() =>
+      'SyncFlushResult(id: ${operation.id}, success: $success, error: $errorMessage)';
+}
+
+/// Abstraction for queuing offline operations and flushing them when online.
+///
+/// Implementations persist the queue across app restarts so that operations
+/// captured while offline survive process termination.
+abstract class SyncQueue {
+  /// Adds [operation] to the tail of the queue.
+  Future<void> enqueue(SyncOperation operation);
+
+  /// Returns all operations currently in the queue, ordered by [SyncOperation.enqueuedAt].
+  Future<List<SyncOperation>> pendingOperations();
+
+  /// Attempts to apply [operation] to the remote via [flush].
+  ///
+  /// On success the operation is removed from the queue.
+  /// On failure the operation's [SyncOperation.attemptCount] and
+  /// [SyncOperation.lastError] are updated and it remains in the queue.
+  Future<SyncFlushResult> process(
+    SyncOperation operation,
+    Future<void> Function(SyncOperation) flush,
+  );
+
+  /// Removes [operation] from the queue regardless of its status.
+  Future<void> remove(String operationId);
+
+  /// Removes all completed and failed operations, retaining only pending ones.
+  Future<void> pruneCompleted();
+
+  /// Returns the number of operations currently in the queue.
+  Future<int> get length;
+}
+
+/// An in-memory [SyncQueue] suitable for testing and development.
+///
+/// Operations are not persisted across process restarts.
+class InMemorySyncQueue implements SyncQueue {
+  final List<SyncOperation> _queue = [];
+
+  @override
+  Future<void> enqueue(SyncOperation operation) async {
+    _queue.add(operation);
+  }
+
+  @override
+  Future<List<SyncOperation>> pendingOperations() async {
+    return _queue.where((op) => op.status == SyncOperationStatus.pending).toList()
+      ..sort((a, b) => a.enqueuedAt.compareTo(b.enqueuedAt));
+  }
+
+  @override
+  Future<SyncFlushResult> process(
+    SyncOperation operation,
+    Future<void> Function(SyncOperation) flush,
+  ) async {
+    final index = _queue.indexWhere((op) => op.id == operation.id);
+    if (index == -1) {
+      return SyncFlushResult.failure(
+        operation: operation,
+        errorMessage: 'Operation not found in queue',
+      );
+    }
+
+    // Mark as in-progress.
+    _queue[index] = _queue[index].copyWith(status: SyncOperationStatus.inProgress);
+
+    try {
+      await flush(operation);
+      _queue[index] = _queue[index].copyWith(
+        status: SyncOperationStatus.completed,
+        attemptCount: operation.attemptCount + 1,
+      );
+      return SyncFlushResult.success(operation: _queue[index]);
+    } catch (e) {
+      _queue[index] = _queue[index].copyWith(
+        status: SyncOperationStatus.failed,
+        attemptCount: operation.attemptCount + 1,
+        lastError: e.toString(),
+      );
+      return SyncFlushResult.failure(operation: _queue[index], errorMessage: e.toString());
+    }
+  }
+
+  @override
+  Future<void> remove(String operationId) async {
+    _queue.removeWhere((op) => op.id == operationId);
+  }
+
+  @override
+  Future<void> pruneCompleted() async {
+    _queue.removeWhere(
+      (op) => op.status == SyncOperationStatus.completed || op.status == SyncOperationStatus.failed,
+    );
+  }
+
+  @override
+  Future<int> get length async => _queue.length;
+}

kell_creations_apps/packages/data/test/data_test.dart

@@ -1,12 +1,627 @@
 import 'package:flutter_test/flutter_test.dart';
-
 import 'package:data/data.dart';
 
+// ── Test doubles ─────────────────────────────────────────────────────────────
+
+/// Simple domain type used across all tests.
+class _Item {
+  final String id;
+  final String name;
+  const _Item(this.id, this.name);
+  @override
+  String toString() => '_Item($id, $name)';
+}
+
+/// Minimal [DataMapper] implementation for tests.
+class _ItemMapper extends DataMapper<_Item, Map<String, dynamic>> {
+  @override
+  _Item fromRemote(Map<String, dynamic> remote) {
+    final id = remote['id'];
+    final name = remote['name'];
+    if (id == null || name == null) {
+      throw DataMappingException(field: 'id/name', message: 'Required fields missing');
+    }
+    return _Item(id as String, name as String);
+  }
+
+  @override
+  Map<String, dynamic> toRemote(_Item local) => {'id': local.id, 'name': local.name};
+}
+
+/// A [ConflictResolver] that always merges by concatenating names.
+class _MergeResolver implements ConflictResolver<_Item> {
+  const _MergeResolver();
+
+  @override
+  ConflictResult<_Item> resolve({
+    required _Item local,
+    required _Item remote,
+    required DateTime localModifiedAt,
+    required DateTime remoteModifiedAt,
+  }) {
+    return ConflictResult.merged(
+      merged: _Item(local.id, '${local.name}+${remote.name}'),
+      reason: 'merged names',
+    );
+  }
+}
+
 void main() {
-  test('adds one to input values', () {
-    final calculator = Calculator();
-    expect(calculator.addOne(2), 3);
-    expect(calculator.addOne(-7), -6);
-    expect(calculator.addOne(0), 1);
+  // ── LocalCache / InMemoryCache ────────────────────────────────────────────
+
+  group('InMemoryCache', () {
+    late InMemoryCache<String> cache;
+
+    setUp(() => cache = InMemoryCache<String>());
+    tearDown(() async => cache.dispose());
+
+    test('put and get returns stored value', () async {
+      await cache.put('k', 'hello');
+      expect(await cache.get('k'), 'hello');
+    });
+
+    test('get returns null for missing key', () async {
+      expect(await cache.get('missing'), isNull);
+    });
+
+    test('containsKey returns true for present key', () async {
+      await cache.put('k', 'v');
+      expect(await cache.containsKey('k'), isTrue);
+    });
+
+    test('containsKey returns false for missing key', () async {
+      expect(await cache.containsKey('missing'), isFalse);
+    });
+
+    test('remove deletes the entry', () async {
+      await cache.put('k', 'v');
+      await cache.remove('k');
+      expect(await cache.get('k'), isNull);
+    });
+
+    test('clear removes all entries', () async {
+      await cache.put('a', '1');
+      await cache.put('b', '2');
+      await cache.clear();
+      expect(await cache.keys(), isEmpty);
+    });
+
+    test('keys returns all non-expired keys', () async {
+      await cache.put('x', '1');
+      await cache.put('y', '2');
+      final keys = await cache.keys();
+      expect(keys, containsAll(['x', 'y']));
+    });
+
+    test('entry expires after ttl', () async {
+      await cache.put('k', 'v', ttl: const Duration(milliseconds: 1));
+      await Future<void>.delayed(const Duration(milliseconds: 10));
+      expect(await cache.get('k'), isNull);
+    });
+
+    test('containsKey returns false for expired entry', () async {
+      await cache.put('k', 'v', ttl: const Duration(milliseconds: 1));
+      await Future<void>.delayed(const Duration(milliseconds: 10));
+      expect(await cache.containsKey('k'), isFalse);
+    });
+
+    test('entry without ttl does not expire', () async {
+      await cache.put('k', 'persistent');
+      await Future<void>.delayed(const Duration(milliseconds: 10));
+      expect(await cache.get('k'), 'persistent');
+    });
+
+    test('dispose clears all entries', () async {
+      await cache.put('k', 'v');
+      await cache.dispose();
+      expect(await cache.keys(), isEmpty);
+    });
+
+    test('overwriting a key replaces the value', () async {
+      await cache.put('k', 'first');
+      await cache.put('k', 'second');
+      expect(await cache.get('k'), 'second');
+    });
+  });
+
+  // ── SyncQueue / InMemorySyncQueue ─────────────────────────────────────────
+
+  group('SyncOperation', () {
+    final op = SyncOperation(
+      id: 'op-1',
+      type: 'createOrder',
+      payload: {'orderId': 42},
+      enqueuedAt: DateTime(2026, 7, 11),
+    );
+
+    test('stores all fields with defaults', () {
+      expect(op.id, 'op-1');
+      expect(op.type, 'createOrder');
+      expect(op.payload['orderId'], 42);
+      expect(op.status, SyncOperationStatus.pending);
+      expect(op.attemptCount, 0);
+      expect(op.lastError, isNull);
+    });
+
+    test('copyWith replaces specified fields', () {
+      final updated = op.copyWith(
+        status: SyncOperationStatus.failed,
+        attemptCount: 2,
+        lastError: 'timeout',
+      );
+      expect(updated.status, SyncOperationStatus.failed);
+      expect(updated.attemptCount, 2);
+      expect(updated.lastError, 'timeout');
+      expect(updated.id, op.id);
+    });
+
+    test('toString includes id, type, status, attempts', () {
+      expect(op.toString(), contains('op-1'));
+      expect(op.toString(), contains('createOrder'));
+    });
+  });
+
+  group('SyncFlushResult', () {
+    final op = SyncOperation(
+      id: 'op-1',
+      type: 'adjustInventory',
+      payload: {},
+      enqueuedAt: DateTime(2026, 7, 11),
+    );
+
+    test('success constructor sets success true and no error', () {
+      final result = SyncFlushResult.success(operation: op);
+      expect(result.success, isTrue);
+      expect(result.errorMessage, isNull);
+    });
+
+    test('failure constructor sets success false and error message', () {
+      final result = SyncFlushResult.failure(operation: op, errorMessage: 'network error');
+      expect(result.success, isFalse);
+      expect(result.errorMessage, 'network error');
+    });
+
+    test('toString includes operation id and success flag', () {
+      final result = SyncFlushResult.success(operation: op);
+      expect(result.toString(), contains('op-1'));
+      expect(result.toString(), contains('true'));
+    });
+  });
+
+  group('InMemorySyncQueue', () {
+    late InMemorySyncQueue queue;
+
+    SyncOperation op0(String id) =>
+        SyncOperation(id: id, type: 'test', payload: {}, enqueuedAt: DateTime(2026, 7, 11));
+
+    setUp(() => queue = InMemorySyncQueue());
+
+    test('enqueue adds operation and length increases', () async {
+      await queue.enqueue(op0('a'));
+      expect(await queue.length, 1);
+    });
+
+    test('pendingOperations returns only pending ops', () async {
+      await queue.enqueue(op0('a'));
+      await queue.enqueue(op0('b'));
+      final pending = await queue.pendingOperations();
+      expect(pending.length, 2);
+      expect(pending.every((op) => op.status == SyncOperationStatus.pending), isTrue);
+    });
+
+    test('process succeeds and marks operation completed', () async {
+      final op = op0('a');
+      await queue.enqueue(op);
+      final result = await queue.process(op, (_) async {});
+      expect(result.success, isTrue);
+      expect(result.operation.status, SyncOperationStatus.completed);
+      expect(result.operation.attemptCount, 1);
+    });
+
+    test('process failure marks operation failed with error', () async {
+      final op = op0('a');
+      await queue.enqueue(op);
+      final result = await queue.process(op, (_) async => throw Exception('boom'));
+      expect(result.success, isFalse);
+      expect(result.operation.status, SyncOperationStatus.failed);
+      expect(result.errorMessage, contains('boom'));
+      expect(result.operation.attemptCount, 1);
+    });
+
+    test('process returns failure for unknown operation id', () async {
+      final op = op0('unknown');
+      final result = await queue.process(op, (_) async {});
+      expect(result.success, isFalse);
+      expect(result.errorMessage, contains('not found'));
+    });
+
+    test('remove deletes operation from queue', () async {
+      await queue.enqueue(op0('a'));
+      await queue.remove('a');
+      expect(await queue.length, 0);
+    });
+
+    test('pruneCompleted removes completed and failed ops', () async {
+      final opA = op0('a');
+      final opB = op0('b');
+      final opC = op0('c');
+      await queue.enqueue(opA);
+      await queue.enqueue(opB);
+      await queue.enqueue(opC);
+      await queue.process(opA, (_) async {}); // completed
+      await queue.process(opB, (_) async => throw Exception('err')); // failed
+      // opC remains pending
+      await queue.pruneCompleted();
+      expect(await queue.length, 1);
+      final pending = await queue.pendingOperations();
+      expect(pending.first.id, 'c');
+    });
+
+    test('pendingOperations excludes completed operations', () async {
+      final op = op0('a');
+      await queue.enqueue(op);
+      await queue.process(op, (_) async {});
+      final pending = await queue.pendingOperations();
+      expect(pending, isEmpty);
+    });
+  });
+
+  // ── ConflictResolver ──────────────────────────────────────────────────────
+
+  group('ConflictResult', () {
+    const item = _Item('1', 'Widget');
+
+    test('useLocal constructor sets resolution and value', () {
+      final result = ConflictResult.useLocal(local: item, reason: 'test');
+      expect(result.resolution, ConflictResolution.useLocal);
+      expect(result.resolvedValue, item);
+      expect(result.reason, 'test');
+    });
+
+    test('useRemote constructor sets resolution and value', () {
+      final result = ConflictResult.useRemote(remote: item, reason: 'test');
+      expect(result.resolution, ConflictResolution.useRemote);
+      expect(result.resolvedValue, item);
+    });
+
+    test('merged constructor sets resolution and value', () {
+      final result = ConflictResult.merged(merged: item, reason: 'merged');
+      expect(result.resolution, ConflictResolution.merge);
+      expect(result.resolvedValue, item);
+    });
+
+    test('requiresReview constructor sets resolution and null value', () {
+      const result = ConflictResult<_Item>.requiresReview(reason: 'conflict');
+      expect(result.resolution, ConflictResolution.requiresOperatorReview);
+      expect(result.resolvedValue, isNull);
+    });
+
+    test('toString includes resolution and reason', () {
+      final result = ConflictResult.useLocal(local: item, reason: 'newer');
+      expect(result.toString(), contains('useLocal'));
+      expect(result.toString(), contains('newer'));
+    });
+  });
+
+  group('LastWriteWinsResolver', () {
+    const resolver = LastWriteWinsResolver<_Item>();
+    const local = _Item('1', 'Local');
+    const remote = _Item('1', 'Remote');
+    final older = DateTime(2026, 1, 1);
+    final newer = DateTime(2026, 7, 11);
+
+    test('prefers local when local is newer', () {
+      final result = resolver.resolve(
+        local: local,
+        remote: remote,
+        localModifiedAt: newer,
+        remoteModifiedAt: older,
+      );
+      expect(result.resolution, ConflictResolution.useLocal);
+      expect(result.resolvedValue, local);
+    });
+
+    test('prefers remote when remote is newer', () {
+      final result = resolver.resolve(
+        local: local,
+        remote: remote,
+        localModifiedAt: older,
+        remoteModifiedAt: newer,
+      );
+      expect(result.resolution, ConflictResolution.useRemote);
+      expect(result.resolvedValue, remote);
+    });
+
+    test('prefers remote when timestamps are equal', () {
+      final result = resolver.resolve(
+        local: local,
+        remote: remote,
+        localModifiedAt: older,
+        remoteModifiedAt: older,
+      );
+      expect(result.resolution, ConflictResolution.useRemote);
+    });
+  });
+
+  group('LocalAlwaysWinsResolver', () {
+    const resolver = LocalAlwaysWinsResolver<_Item>();
+    const local = _Item('1', 'Local');
+    const remote = _Item('1', 'Remote');
+    final t = DateTime(2026, 7, 11);
+
+    test('always returns local regardless of timestamps', () {
+      final result = resolver.resolve(
+        local: local,
+        remote: remote,
+        localModifiedAt: t,
+        remoteModifiedAt: t.add(const Duration(days: 1)),
+      );
+      expect(result.resolution, ConflictResolution.useLocal);
+      expect(result.resolvedValue, local);
+    });
+  });
+
+  group('RemoteAlwaysWinsResolver', () {
+    const resolver = RemoteAlwaysWinsResolver<_Item>();
+    const local = _Item('1', 'Local');
+    const remote = _Item('1', 'Remote');
+    final t = DateTime(2026, 7, 11);
+
+    test('always returns remote regardless of timestamps', () {
+      final result = resolver.resolve(
+        local: local,
+        remote: remote,
+        localModifiedAt: t.add(const Duration(days: 1)),
+        remoteModifiedAt: t,
+      );
+      expect(result.resolution, ConflictResolution.useRemote);
+      expect(result.resolvedValue, remote);
+    });
+  });
+
+  group('Custom ConflictResolver (merge)', () {
+    const resolver = _MergeResolver();
+    const local = _Item('1', 'A');
+    const remote = _Item('1', 'B');
+    final t = DateTime(2026, 7, 11);
+
+    test('merge resolver produces merged value', () {
+      final result = resolver.resolve(
+        local: local,
+        remote: remote,
+        localModifiedAt: t,
+        remoteModifiedAt: t,
+      );
+      expect(result.resolution, ConflictResolution.merge);
+      expect((result.resolvedValue as _Item).name, 'A+B');
+    });
+  });
+
+  // ── ChangeTracker / InMemoryChangeTracker ─────────────────────────────────
+
+  group('TrackedChange', () {
+    final now = DateTime(2026, 7, 11);
+    const item = _Item('1', 'Widget');
+
+    test('stores all fields', () {
+      final change = TrackedChange<_Item>(
+        id: '1',
+        value: item,
+        state: ChangeState.created,
+        changedAt: now,
+      );
+      expect(change.id, '1');
+      expect(change.value, item);
+      expect(change.state, ChangeState.created);
+      expect(change.changedAt, now);
+      expect(change.syncError, isNull);
+    });
+
+    test('copyWith replaces specified fields', () {
+      final change = TrackedChange<_Item>(
+        id: '1',
+        value: item,
+        state: ChangeState.modified,
+        changedAt: now,
+      );
+      final updated = change.copyWith(state: ChangeState.syncError, syncError: 'err');
+      expect(updated.state, ChangeState.syncError);
+      expect(updated.syncError, 'err');
+      expect(updated.id, '1');
+    });
+
+    test('toString includes id, state, changedAt', () {
+      final change = TrackedChange<_Item>(
+        id: '1',
+        value: item,
+        state: ChangeState.created,
+        changedAt: now,
+      );
+      expect(change.toString(), contains('1'));
+      expect(change.toString(), contains('created'));
+    });
+  });
+
+  group('InMemoryChangeTracker', () {
+    late InMemoryChangeTracker<_Item> tracker;
+    const item = _Item('1', 'Widget');
+    const updated = _Item('1', 'Widget Pro');
+
+    setUp(() => tracker = InMemoryChangeTracker<_Item>());
+
+    test('trackCreated records created state', () async {
+      await tracker.trackCreated('1', item);
+      final change = await tracker.getChange('1');
+      expect(change?.state, ChangeState.created);
+      expect(change?.value, item);
+    });
+
+    test('trackModified records modified state', () async {
+      await tracker.trackModified('1', updated);
+      final change = await tracker.getChange('1');
+      expect(change?.state, ChangeState.modified);
+    });
+
+    test('trackModified on created record preserves created state', () async {
+      await tracker.trackCreated('1', item);
+      await tracker.trackModified('1', updated);
+      final change = await tracker.getChange('1');
+      expect(change?.state, ChangeState.created);
+    });
+
+    test('trackDeleted records deleted state', () async {
+      await tracker.trackCreated('1', item);
+      await tracker.trackDeleted('1');
+      final change = await tracker.getChange('1');
+      expect(change?.state, ChangeState.deleted);
+      expect(change?.value, isNull);
+    });
+
+    test('markSynced removes the change', () async {
+      await tracker.trackCreated('1', item);
+      await tracker.markSynced('1');
+      expect(await tracker.getChange('1'), isNull);
+    });
+
+    test('markSyncError updates state and error message', () async {
+      await tracker.trackModified('1', item);
+      await tracker.markSyncError('1', 'network timeout');
+      final change = await tracker.getChange('1');
+      expect(change?.state, ChangeState.syncError);
+      expect(change?.syncError, 'network timeout');
+    });
+
+    test('pendingChanges returns all non-synced changes', () async {
+      await tracker.trackCreated('1', item);
+      await tracker.trackModified('2', updated);
+      final pending = await tracker.pendingChanges();
+      expect(pending.length, 2);
+    });
+
+    test('hasPendingChanges returns true when changes exist', () async {
+      await tracker.trackCreated('1', item);
+      expect(await tracker.hasPendingChanges, isTrue);
+    });
+
+    test('hasPendingChanges returns false when empty', () async {
+      expect(await tracker.hasPendingChanges, isFalse);
+    });
+
+    test('clear removes all tracked changes', () async {
+      await tracker.trackCreated('1', item);
+      await tracker.trackModified('2', updated);
+      await tracker.clear();
+      expect(await tracker.hasPendingChanges, isFalse);
+    });
+
+    test('getChange returns null for untracked id', () async {
+      expect(await tracker.getChange('unknown'), isNull);
+    });
+
+    test('markSyncError on untracked id is a no-op', () async {
+      // Should not throw.
+      await tracker.markSyncError('unknown', 'error');
+      expect(await tracker.hasPendingChanges, isFalse);
+    });
+  });
+
+  // ── DataMapper / DataMappingException ─────────────────────────────────────
+
+  group('DataMapper (_ItemMapper)', () {
+    final mapper = _ItemMapper();
+
+    test('fromRemote maps valid remote DTO to domain object', () {
+      final item = mapper.fromRemote({'id': 'i1', 'name': 'Candle'});
+      expect(item.id, 'i1');
+      expect(item.name, 'Candle');
+    });
+
+    test('toRemote maps domain object to remote DTO', () {
+      const item = _Item('i1', 'Candle');
+      final dto = mapper.toRemote(item);
+      expect(dto['id'], 'i1');
+      expect(dto['name'], 'Candle');
+    });
+
+    test('fromRemoteList maps a list of DTOs', () {
+      final items = mapper.fromRemoteList([
+        {'id': 'a', 'name': 'A'},
+        {'id': 'b', 'name': 'B'},
+      ]);
+      expect(items.length, 2);
+      expect(items[0].id, 'a');
+      expect(items[1].name, 'B');
+    });
+
+    test('toRemoteList maps a list of domain objects', () {
+      const items = [_Item('a', 'A'), _Item('b', 'B')];
+      final dtos = mapper.toRemoteList(items);
+      expect(dtos.length, 2);
+      expect(dtos[0]['id'], 'a');
+      expect(dtos[1]['name'], 'B');
+    });
+
+    test('fromRemote throws DataMappingException for missing fields', () {
+      expect(
+        () => mapper.fromRemote({'id': null, 'name': null}),
+        throwsA(isA<DataMappingException>()),
+      );
+    });
+  });
+
+  group('DataMappingException', () {
+    test('stores field, message, and rawValue', () {
+      const ex = DataMappingException(
+        field: 'status',
+        message: 'Unknown status value',
+        rawValue: 'bogus',
+      );
+      expect(ex.field, 'status');
+      expect(ex.message, 'Unknown status value');
+      expect(ex.rawValue, 'bogus');
+    });
+
+    test('rawValue defaults to null', () {
+      const ex = DataMappingException(field: 'id', message: 'Missing id');
+      expect(ex.rawValue, isNull);
+    });
+
+    test('toString includes field and message', () {
+      const ex = DataMappingException(field: 'price', message: 'Negative price');
+      expect(ex.toString(), contains('price'));
+      expect(ex.toString(), contains('Negative price'));
+    });
+
+    test('toString includes rawValue when present', () {
+      const ex = DataMappingException(field: 'qty', message: 'Bad qty', rawValue: -5);
+      expect(ex.toString(), contains('-5'));
+    });
+
+    test('is an Exception', () {
+      const ex = DataMappingException(field: 'x', message: 'y');
+      expect(ex, isA<Exception>());
+    });
+  });
+
+  // ── Barrel smoke test ─────────────────────────────────────────────────────
+
+  group('data barrel exports', () {
+    test('all public types are accessible via package:data/data.dart', () {
+      // LocalCache
+      expect(InMemoryCache<String>.new, isNotNull);
+      // SyncQueue
+      expect(InMemorySyncQueue.new, isNotNull);
+      expect(SyncOperationStatus.values, isNotEmpty);
+      // ConflictResolver
+      expect(LastWriteWinsResolver<String>.new, isNotNull);
+      expect(LocalAlwaysWinsResolver<String>.new, isNotNull);
+      expect(RemoteAlwaysWinsResolver<String>.new, isNotNull);
+      expect(ConflictResolution.values, isNotEmpty);
+      // ChangeTracker
+      expect(InMemoryChangeTracker<String>.new, isNotNull);
+      expect(ChangeState.values, isNotEmpty);
+      // DataMapper
+      expect(DataMappingException.new, isNotNull);
+    });
   });
 }

kell_creations_apps/tools/run_all_tests.sh

@@ -20,6 +20,7 @@ TESTABLE=(
   packages/core
   packages/design_system
   packages/integrations
+  packages/data
   packages/feature_wordpress
   packages/feature_inventory
   packages/feature_orders
@@ -32,6 +33,7 @@ ANALYZABLE=(
   packages/core
   packages/design_system
   packages/integrations
+  packages/data
   packages/feature_wordpress
   packages/feature_inventory
   packages/feature_orders