diff --git a/analysis_options.yaml b/analysis_options.yaml
index 0d29021..2ea7792 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -23,6 +23,9 @@ linter:
   rules:
     # avoid_print: false  # Uncomment to disable the `avoid_print` rule
     # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
+    # ?'key': value applies ? to the key (never null for string literals);
+    # the if (x != null) form is correct for nullable-value map entries.
+    use_null_aware_elements: false
 
 # Additional information about this file can be found at
 # https://dart.dev/guides/language/analysis-options
diff --git a/lib/data/api/notes_api.dart b/lib/data/api/notes_api.dart
index 139eb0f..048cdf7 100644
--- a/lib/data/api/notes_api.dart
+++ b/lib/data/api/notes_api.dart
@@ -38,7 +38,7 @@ class NotesApi {
         'title': title,
         'body': body,
         'tags': tags,
-        ?'project_id': projectId,
+        if (projectId != null) 'project_id': projectId,
       });
       return Note.fromJson(response.data as Map<String, dynamic>);
     } on DioException catch (e) {
@@ -59,7 +59,7 @@ class NotesApi {
         'title': title,
         'body': body,
         'tags': tags,
-        if (clearProject) 'project_id': null else ?'project_id': projectId,
+        if (clearProject) 'project_id': null else if (projectId != null) 'project_id': projectId,
       });
       return Note.fromJson(response.data as Map<String, dynamic>);
     } on DioException catch (e) {
diff --git a/lib/data/api/projects_api.dart b/lib/data/api/projects_api.dart
index 6e7a08b..c28dbd4 100644
--- a/lib/data/api/projects_api.dart
+++ b/lib/data/api/projects_api.dart
@@ -44,7 +44,7 @@ class ProjectsApi {
         if (description != null && description.isNotEmpty)
           'description': description,
         if (goal != null && goal.isNotEmpty) 'goal': goal,
-        ?'color': color,
+        if (color != null) 'color': color,
       });
       return Project.fromJson(response.data as Map<String, dynamic>);
     } on DioException catch (e) {
diff --git a/lib/data/api/tasks_api.dart b/lib/data/api/tasks_api.dart
index 463202c..bb098b8 100644
--- a/lib/data/api/tasks_api.dart
+++ b/lib/data/api/tasks_api.dart
@@ -43,8 +43,8 @@ class TasksApi {
         'status': status.value,
         'priority': priority.value,
         'due_date': dueDate?.toIso8601String(),
-        ?'project_id': projectId,
-        ?'parent_id': parentId,
+        if (projectId != null) 'project_id': projectId,
+        if (parentId != null) 'parent_id': parentId,
       });
       return Task.fromJson(response.data as Map<String, dynamic>);
     } on DioException catch (e) {