diff --git a/pydantic2ts/cli/script.py b/pydantic2ts/cli/script.py
index 8518395..19a341f 100644
--- a/pydantic2ts/cli/script.py
+++ b/pydantic2ts/cli/script.py
@@ -14,10 +14,6 @@
 
 from pydantic import BaseModel, Extra, create_model
 
-try:
-    from pydantic.generics import GenericModel
-except ImportError:
-    GenericModel = None
 
 logger = logging.getLogger("pydantic2ts")
 
@@ -65,8 +61,9 @@ def is_concrete_pydantic_model(obj) -> bool:
         return False
     elif obj is BaseModel:
         return False
-    elif GenericModel and issubclass(obj, GenericModel):
-        return bool(obj.__concrete__)
+    # Generic model was removed
+    # elif GenericModel and issubclass(obj, GenericModel):
+    #     return bool(obj.__concrete__)
     else:
         return issubclass(obj, BaseModel)
 
@@ -137,6 +134,11 @@ def clean_schema(schema: Dict[str, Any]) -> None:
     for prop in schema.get("properties", {}).values():
         prop.pop("title", None)
 
+        # Work around to produce Tuples just like Arrays since json2ts doesn't support the
+        # prefixItems json openAPI spec
+        if "prefixItems" in prop:
+            prop["items"] = prop["prefixItems"]
+
     if "enum" in schema and schema.get("description") == "An enumeration.":
         del schema["description"]
 
@@ -152,22 +154,24 @@ def generate_json_schema(models: List[Type[BaseModel]]) -> str:
     '[k: string]: any' from being added to every interface. This change is reverted
     once the schema has been generated.
     """
-    model_extras = [getattr(m.Config, "extra", None) for m in models]
+    model_extras = [m.model_config.get("extra", None) for m in models]
 
     try:
         for m in models:
-            if getattr(m.Config, "extra", None) != Extra.allow:
-                m.Config.extra = Extra.forbid
+            if m.model_config.get("extra", None) != "allow":
+                m.model_config["extra"] = "forbid"
 
         master_model = create_model(
             "_Master_", **{m.__name__: (m, ...) for m in models}
         )
-        master_model.Config.extra = Extra.forbid
-        master_model.Config.schema_extra = staticmethod(clean_schema)
+        master_model.model_config["extra"] = "forbid"
+        master_model.model_config["json_schema_extra"] = staticmethod(clean_schema)
+
+        schema = master_model.model_json_schema()
 
-        schema = json.loads(master_model.schema_json())
+        # prefixItems
 
-        for d in schema.get("definitions", {}).values():
+        for d in schema.get("$defs", {}).values():
             clean_schema(d)
 
         return json.dumps(schema, indent=2)
@@ -175,7 +179,7 @@ def generate_json_schema(models: List[Type[BaseModel]]) -> str:
     finally:
         for m, x in zip(models, model_extras):
             if x is not None:
-                m.Config.extra = x
+                m.model_config["extra"] = x
 
 
 def generate_typescript_defs(
@@ -281,3 +285,4 @@ def main() -> None:
 
 if __name__ == "__main__":
     main()
+
diff --git a/setup.py b/setup.py
index dff85f4..7777cdc 100644
--- a/setup.py
+++ b/setup.py
@@ -25,7 +25,7 @@ def readme():
 
 setup(
     name="pydantic-to-typescript",
-    version="1.0.10",
+    version="2.0.0",
     description="Convert pydantic models to typescript interfaces",
     license="MIT",
     long_description=readme(),
diff --git a/tests/expected_results/excluding_models/output.ts b/tests/expected_results/excluding_models/output.ts
index 451bb73..af83361 100644
--- a/tests/expected_results/excluding_models/output.ts
+++ b/tests/expected_results/excluding_models/output.ts
@@ -7,6 +7,6 @@
 
 export interface Profile {
   username: string;
-  age?: number;
+  age: number | null;
   hobbies: string[];
 }
diff --git a/tests/expected_results/generics/input.py b/tests/expected_results/generics/input.py
index a37bc55..61a67a8 100644
--- a/tests/expected_results/generics/input.py
+++ b/tests/expected_results/generics/input.py
@@ -2,7 +2,6 @@
 from typing import Generic, TypeVar, Optional, List, Type, cast, Union
 
 from pydantic import BaseModel
-from pydantic.generics import GenericModel
 
 T = TypeVar("T")
 
@@ -12,7 +11,7 @@ class Error(BaseModel):
     message: str
 
 
-class ApiResponse(GenericModel, Generic[T]):
+class ApiResponse(BaseModel, Generic[T]):
     data: Optional[T]
     error: Optional[Error]
 
diff --git a/tests/expected_results/generics/output.ts b/tests/expected_results/generics/output.ts
index 5da2624..79b3b5f 100644
--- a/tests/expected_results/generics/output.ts
+++ b/tests/expected_results/generics/output.ts
@@ -5,6 +5,14 @@
 /* Do not modify it by hand - just update the pydantic models and then re-run the script
 */
 
+export interface ApiResponse {
+  data: unknown;
+  error: Error | null;
+}
+export interface Error {
+  code: number;
+  message: string;
+}
 export interface Article {
   author: User;
   content: string;
@@ -14,17 +22,13 @@ export interface User {
   name: string;
   email: string;
 }
-export interface Error {
-  code: number;
-  message: string;
-}
 export interface ListArticlesResponse {
-  data?: Article[];
-  error?: Error;
+  data: Article[] | null;
+  error: Error | null;
 }
 export interface ListUsersResponse {
-  data?: User[];
-  error?: Error;
+  data: User[] | null;
+  error: Error | null;
 }
 export interface UserProfile {
   name: string;
@@ -34,6 +38,6 @@ export interface UserProfile {
   age: number;
 }
 export interface UserProfileResponse {
-  data?: UserProfile;
-  error?: Error;
+  data: UserProfile | null;
+  error: Error | null;
 }
diff --git a/tests/expected_results/single_module/output.ts b/tests/expected_results/single_module/output.ts
index 4defc90..56ea42c 100644
--- a/tests/expected_results/single_module/output.ts
+++ b/tests/expected_results/single_module/output.ts
@@ -15,6 +15,6 @@ export interface LoginResponseData {
 }
 export interface Profile {
   username: string;
-  age?: number;
+  age: number | null;
   hobbies: string[];
 }