diff --git a/longs/api.py b/longs/api.py
index 6c1bc513..75a5604b 100644
--- a/longs/api.py
+++ b/longs/api.py
@@ -14,19 +14,20 @@ router = Router()
 
 
 class QuestionSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Question
 
-        #model_fields = ["question", "history", "feedback", "normal", "laterality"]
-        model_fields = "__all__"
+        # Use `fields` per newer ninja ModelSchema API
+        #fields = ["question", "history", "feedback", "normal", "laterality"]
+        fields = "__all__"
 
-        #model_exclude = ["answers"]
+        #exclude = ["answers"]
 
 class ExamSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Exam
 
-        model_fields = ["id", "name", "active", "publish_results"]
+        fields = ["id", "name", "active", "publish_results"]
 
 @router.get('/')
 def list_questions(request):
diff --git a/physics/api.py b/physics/api.py
index f46306a1..abba04ea 100644
--- a/physics/api.py
+++ b/physics/api.py
@@ -15,19 +15,19 @@ router = Router()
 
 
 class QuestionSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Question
 
-        #model_fields = ["question", "history", "feedback", "normal", "laterality"]
-        model_fields = "__all__"
+        # Use `fields` per newer ninja ModelSchema API
+        fields = "__all__"
 
-        #model_exclude = ["answers"]
+        #exclude = ["answers"]
 
 class ExamSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Exam
 
-        model_fields = ["id", "name", "active", "publish_results"]
+        fields = ["id", "name", "active", "publish_results"]
 
 @router.get('/')
 def list_questions(request):
diff --git a/rapids/api.py b/rapids/api.py
index b0f4875c..2d78ddcd 100644
--- a/rapids/api.py
+++ b/rapids/api.py
@@ -15,19 +15,19 @@ router = Router()
 
 
 class RapidSchema(ModelSchema):
-    class Config:
+    # `ninja` newer versions require an inner `Meta` class instead of `Config`
+    # for ModelSchema. Replace `Config` with `Meta` to be compatible.
+    class Meta:
         model = Rapid
-
-        #model_fields = ["question", "history", "feedback", "normal", "laterality"]
-        model_fields = "__all__"
-
-        #model_exclude = ["answers"]
+        #model_fields (old API) -> use `fields` per newer ninja ModelSchema API
+        #fields can be a list of field names or the string "__all__".
+        #fields = ["question", "history", "feedback", "normal", "laterality"]
+        fields = "__all__"
 
 class ExamSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Exam
-
-        model_fields = ["id", "name", "active", "publish_results"]
+        fields = ["id", "name", "active", "publish_results"]
 
 @router.get('/')
 def list_rapids(request):
diff --git a/sbas/api.py b/sbas/api.py
index 2da50baf..c2b3c568 100644
--- a/sbas/api.py
+++ b/sbas/api.py
@@ -15,19 +15,18 @@ router = Router()
 
 
 class QuestionSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Question
 
-        #model_fields = ["question", "history", "feedback", "normal", "laterality"]
-        model_fields = "__all__"
+        fields = "__all__"
 
-        #model_exclude = ["answers"]
+        #exclude = ["answers"]
 
 class ExamSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Exam
 
-        model_fields = ["id", "name", "active", "publish_results"]
+        fields = ["id", "name", "active", "publish_results"]
 
 @router.get('/')
 def list_questions(request):
diff --git a/shorts/api.py b/shorts/api.py
index 49736127..79b0fd56 100644
--- a/shorts/api.py
+++ b/shorts/api.py
@@ -15,19 +15,19 @@ router = Router()
 
 
 class QuestionSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Question
 
-        #model_fields = ["question", "history", "feedback", "normal", "laterality"]
-        model_fields = "__all__"
+        # Use `fields` per newer ninja ModelSchema API
+        fields = "__all__"
 
-        #model_exclude = ["answers"]
+        #exclude = ["answers"]
 
 class ExamSchema(ModelSchema):
-    class Config:
+    class Meta:
         model = Exam
 
-        model_fields = ["id", "name", "active", "publish_results"]
+        fields = ["id", "name", "active", "publish_results"]
 
 @router.get('/')
 def list_questions(request):