diff --git a/cloudquery/sdk/scalar/scalar_factory.py b/cloudquery/sdk/scalar/scalar_factory.py
index 4b390c1..6eabaca 100644
--- a/cloudquery/sdk/scalar/scalar_factory.py
+++ b/cloudquery/sdk/scalar/scalar_factory.py
@@ -1,5 +1,6 @@
 import pyarrow as pa
-from .scalar import ScalarInvalidTypeError
+
+from cloudquery.sdk.types import UUIDType, JSONType
 from .binary import Binary
 from .bool import Bool
 from .date32 import Date32
@@ -7,11 +8,11 @@
 from .float import Float
 from .int import Int
 from .list import List
+from .scalar import ScalarInvalidTypeError
 from .string import String
 from .timestamp import Timestamp
 from .uint import Uint
 from .uuid import UUID
-from cloudquery.sdk.types import UUIDType, JSONType
 
 
 class ScalarFactory:
@@ -85,9 +86,9 @@ def new_scalar(self, dt: pa.DataType):
         #     return ()
         elif dt_id == pa.types.lib.Type_TIMESTAMP:
             return Timestamp()
-        elif dt == UUIDType:
+        elif dt == UUIDType():
             return UUID()
-        elif dt == JSONType:
+        elif dt == JSONType():
             return String()
         else:
             raise ScalarInvalidTypeError("Invalid type {} for scalar".format(dt))
diff --git a/cloudquery/sdk/scheduler/scheduler.py b/cloudquery/sdk/scheduler/scheduler.py
index 8f713ba..ae9b7ba 100644
--- a/cloudquery/sdk/scheduler/scheduler.py
+++ b/cloudquery/sdk/scheduler/scheduler.py
@@ -1,18 +1,16 @@
-from typing import List, Generator, Any
 import queue
-import time
+from concurrent import futures
+from typing import List, Generator, Any
+
 import structlog
-from enum import Enum
-from cloudquery.sdk.schema import Table, Resource
+
 from cloudquery.sdk.message import (
     SyncMessage,
     SyncInsertMessage,
     SyncMigrateTableMessage,
 )
-from concurrent import futures
-from typing import Generator
+from cloudquery.sdk.schema import Resource
 from .table_resolver import TableResolver
-import traceback
 
 QUEUE_PER_WORKER = 100
 
@@ -192,4 +190,4 @@ def sync(
                     break
                 continue
             yield message
-        thread.shutdown()
+        thread.shutdown(wait=True)
diff --git a/requirements.txt b/requirements.txt
index 9b267c9..945c9b4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,21 +1 @@
-cloudquery-plugin-pb==0.0.14
-exceptiongroup==1.1.2
-black==23.7.0
-grpcio==1.56.2
-grpcio-tools==1.56.2
-iniconfig==2.0.0
-Jinja2==3.1.2
-MarkupSafe==2.1.3
-numpy==1.25.2
-packaging==23.1
-pandas==2.0.3
-pluggy==1.2.0
-protobuf==4.23.4
-pyarrow==12.0.1
-pytest==7.4.0
-python-dateutil==2.8.2
-pytz==2023.3
-six==1.16.0
-structlog==23.1.0
-tomli==2.0.1
-tzdata==2023.3
+.
\ No newline at end of file
diff --git a/setup.py b/setup.py
index 2be00b2..9d8703f 100644
--- a/setup.py
+++ b/setup.py
@@ -11,10 +11,26 @@
 
 dependencies = [
     "cloudquery-plugin-pb==0.0.14",
-    "pyarrow==12.0.1",
+    "exceptiongroup==1.1.2",
+    "black==23.7.0",
+    "grpcio==1.56.2",
+    "grpcio-tools==1.56.2",
+    "iniconfig==2.0.0",
     "Jinja2==3.1.2",
-    "structlog==23.1.0",
+    "MarkupSafe==2.1.3",
+    "numpy==1.25.2",
+    "packaging==23.1",
     "pandas==2.0.3",
+    "pluggy==1.2.0",
+    "protobuf==4.23.4",
+    "pyarrow==12.0.1",
+    "pytest==7.4.0",
+    "python-dateutil==2.8.2",
+    "pytz==2023.3",
+    "six==1.16.0",
+    "structlog==23.1.0",
+    "tomli==2.0.1",
+    "tzdata==2023.3",
 ]
 url = "https://github.com/cloudquery/plugin-sdk-python"
 
diff --git a/tests/types/__init__.py b/tests/types/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/types/json.py b/tests/types/json.py
new file mode 100644
index 0000000..f0ba704
--- /dev/null
+++ b/tests/types/json.py
@@ -0,0 +1,7 @@
+from cloudquery.sdk.types import JSONType
+
+
+def test_json_type():
+    j = JSONType()
+    # test equality
+    assert j == JSONType()