diff --git a/.github/workflows/cicd.yaml b/.github/workflows/cicd.yaml
index 514e31496..2ab892874 100644
--- a/.github/workflows/cicd.yaml
+++ b/.github/workflows/cicd.yaml
@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.9", "3.10", "3.11"]
     timeout-minutes: 20
 
     services:
@@ -48,7 +48,7 @@ jobs:
           python-version: ${{ matrix.python-version }}
 
       - name: Lint code
-        if: ${{ matrix.python-version == 3.8 }}
+        if: ${{ matrix.python-version == 3.9 }}
         run: |
           python -m pip install pre-commit
           pre-commit run --all-files
diff --git a/.github/workflows/deploy_mkdocs.yml b/.github/workflows/deploy_mkdocs.yml
index b29f0732a..f3d1d951d 100644
--- a/.github/workflows/deploy_mkdocs.yml
+++ b/.github/workflows/deploy_mkdocs.yml
@@ -21,10 +21,10 @@ jobs:
       - name: Checkout main
         uses: actions/checkout@v4
 
-      - name: Set up Python 3.8
+      - name: Set up Python 3.9
         uses: actions/setup-python@v5
         with:
-          python-version: 3.8
+          python-version: 3.9
 
       - name: Install dependencies
         run: |
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 193edc5c7..51588b36c 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -5,6 +5,6 @@ repos:
       - id: ruff
         args: [--fix, --exit-non-zero-on-fix]
   - repo: https://github.com/psf/black
-    rev: 23.3.0
+    rev: 24.1.1
     hooks:
       - id: black
diff --git a/CHANGES.md b/CHANGES.md
index 16bc9a809..a864e6d5b 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,6 +2,9 @@
 
 ## [Unreleased]
 
+* Removing support for Python 3.8
+* Update to pydantic v2 and stac_pydantic v3
+
 ## [2.4.9] - 2023-11-17
 
 ### Added
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index cadb694e9..fd77b3798 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -10,7 +10,7 @@ $ cd stac-fastapi
 $ pip install -e stac_fastapi/api[dev]
 ```
 
-**Python3.8 only**
+**Python3.9 only**
 
 This repo is set to use `pre-commit` to run *ruff*, *pydocstring*, *black* ("uncompromising Python code formatter") and mypy when committing new code.
 
diff --git a/Dockerfile b/Dockerfile
index 2187ac53e..294e13d86 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3.8-slim as base
+FROM python:3.9-slim as base
 
 # Any python libraries that require system libraries to be installed will likely
 # need the following packages in order to build
diff --git a/Dockerfile.docs b/Dockerfile.docs
index e3c7447e5..24c2a7770 100644
--- a/Dockerfile.docs
+++ b/Dockerfile.docs
@@ -1,4 +1,4 @@
-FROM python:3.8-slim
+FROM python:3.9-slim
 
 # build-essential is required to build a wheel for ciso8601
 RUN apt update && apt install -y build-essential
diff --git a/mkdocs.yml b/mkdocs.yml
index 60374dc3b..4811370ac 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -68,7 +68,6 @@ nav:
           - requests: api/stac_fastapi/types/requests.md
           - rfc3339: api/stac_fastapi/types/rfc3339.md
           - search: api/stac_fastapi/types/search.md
-          - stac: api/stac_fastapi/types/stac.md
           - version: api/stac_fastapi/types/version.md
   - Development - Contributing: "contributing.md"
   - Release Notes: "release-notes.md"
diff --git a/stac_fastapi/api/setup.py b/stac_fastapi/api/setup.py
index 1e3b8002f..2e9ba8549 100644
--- a/stac_fastapi/api/setup.py
+++ b/stac_fastapi/api/setup.py
@@ -6,9 +6,6 @@
     desc = f.read()
 
 install_requires = [
-    "attrs",
-    "pydantic[dotenv]<2",
-    "stac_pydantic==2.0.*",
     "brotli_asgi",
     "stac-fastapi.types",
 ]
@@ -32,12 +29,12 @@
     description="An implementation of STAC API based on the FastAPI framework.",
     long_description=desc,
     long_description_content_type="text/markdown",
-    python_requires=">=3.8",
+    python_requires=">=3.9",
     classifiers=[
         "Intended Audience :: Developers",
         "Intended Audience :: Information Technology",
         "Intended Audience :: Science/Research",
-        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
         "License :: OSI Approved :: MIT License",
     ],
     keywords="STAC FastAPI COG",
diff --git a/stac_fastapi/api/stac_fastapi/api/app.py b/stac_fastapi/api/stac_fastapi/api/app.py
index 28fff912c..17585f552 100644
--- a/stac_fastapi/api/stac_fastapi/api/app.py
+++ b/stac_fastapi/api/stac_fastapi/api/app.py
@@ -1,5 +1,6 @@
 """Fastapi app creation."""
-from typing import Any, Dict, List, Optional, Tuple, Type, Union
+
+from typing import Any, Optional, Tuple, Type, Union
 
 import attr
 from brotli_asgi import BrotliMiddleware
@@ -9,7 +10,7 @@
 from stac_pydantic import Collection, Item, ItemCollection
 from stac_pydantic.api import ConformanceClasses, LandingPage
 from stac_pydantic.api.collections import Collections
-from stac_pydantic.version import STAC_VERSION
+from stac_pydantic.api.version import STAC_API_VERSION
 from starlette.responses import JSONResponse, Response
 
 from stac_fastapi.api.errors import DEFAULT_STATUS_CODES, add_exception_handlers
@@ -67,8 +68,8 @@ class StacApi:
 
     settings: ApiSettings = attr.ib()
     client: Union[AsyncBaseCoreClient, BaseCoreClient] = attr.ib()
-    extensions: List[ApiExtension] = attr.ib(default=attr.Factory(list))
-    exceptions: Dict[Type[Exception], int] = attr.ib(
+    extensions: list[ApiExtension] = attr.ib(default=attr.Factory(list))
+    exceptions: dict[Type[Exception], int] = attr.ib(
         default=attr.Factory(lambda: DEFAULT_STATUS_CODES)
     )
     app: FastAPI = attr.ib(
@@ -85,7 +86,7 @@ class StacApi:
     router: APIRouter = attr.ib(default=attr.Factory(APIRouter))
     title: str = attr.ib(default="stac-fastapi")
     api_version: str = attr.ib(default="0.1")
-    stac_version: str = attr.ib(default=STAC_VERSION)
+    stac_version: str = attr.ib(default=STAC_API_VERSION)
     description: str = attr.ib(default="stac-fastapi")
     search_get_request_model: Type[BaseSearchGetRequest] = attr.ib(
         default=BaseSearchGetRequest
@@ -95,12 +96,12 @@ class StacApi:
     )
     pagination_extension = attr.ib(default=TokenPaginationExtension)
     response_class: Type[Response] = attr.ib(default=JSONResponse)
-    middlewares: List = attr.ib(
+    middlewares: list = attr.ib(
         default=attr.Factory(
             lambda: [BrotliMiddleware, CORSMiddleware, ProxyHeaderMiddleware]
         )
     )
-    route_dependencies: List[Tuple[List[Scope], List[Depends]]] = attr.ib(default=[])
+    route_dependencies: list[Tuple[list[Scope], list[Depends]]] = attr.ib(default=[])
 
     def get_extension(self, extension: Type[ApiExtension]) -> Optional[ApiExtension]:
         """Get an extension.
@@ -125,9 +126,9 @@ def register_landing_page(self):
         self.router.add_api_route(
             name="Landing Page",
             path="/",
-            response_model=LandingPage
-            if self.settings.enable_response_models
-            else None,
+            response_model=(
+                LandingPage if self.settings.enable_response_models else None
+            ),
             response_class=self.response_class,
             response_model_exclude_unset=False,
             response_model_exclude_none=True,
@@ -146,9 +147,9 @@ def register_conformance_classes(self):
         self.router.add_api_route(
             name="Conformance Classes",
             path="/conformance",
-            response_model=ConformanceClasses
-            if self.settings.enable_response_models
-            else None,
+            response_model=(
+                ConformanceClasses if self.settings.enable_response_models else None
+            ),
             response_class=self.response_class,
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
@@ -187,9 +188,11 @@ def register_post_search(self):
         self.router.add_api_route(
             name="Search",
             path="/search",
-            response_model=(ItemCollection if not fields_ext else None)
-            if self.settings.enable_response_models
-            else None,
+            response_model=(
+                (ItemCollection if not fields_ext else None)
+                if self.settings.enable_response_models
+                else None
+            ),
             response_class=GeoJSONResponse,
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
@@ -209,9 +212,11 @@ def register_get_search(self):
         self.router.add_api_route(
             name="Search",
             path="/search",
-            response_model=(ItemCollection if not fields_ext else None)
-            if self.settings.enable_response_models
-            else None,
+            response_model=(
+                (ItemCollection if not fields_ext else None)
+                if self.settings.enable_response_models
+                else None
+            ),
             response_class=GeoJSONResponse,
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
@@ -230,9 +235,9 @@ def register_get_collections(self):
         self.router.add_api_route(
             name="Get Collections",
             path="/collections",
-            response_model=Collections
-            if self.settings.enable_response_models
-            else None,
+            response_model=(
+                Collections if self.settings.enable_response_models else None
+            ),
             response_class=self.response_class,
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
@@ -280,9 +285,9 @@ def register_get_item_collection(self):
         self.router.add_api_route(
             name="Get ItemCollection",
             path="/collections/{collection_id}/items",
-            response_model=ItemCollection
-            if self.settings.enable_response_models
-            else None,
+            response_model=(
+                ItemCollection if self.settings.enable_response_models else None
+            ),
             response_class=GeoJSONResponse,
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
@@ -318,7 +323,7 @@ def register_core(self):
         self.register_get_collection()
         self.register_get_item_collection()
 
-    def customize_openapi(self) -> Optional[Dict[str, Any]]:
+    def customize_openapi(self) -> Optional[dict[str, Any]]:
         """Customize openapi schema."""
         if self.app.openapi_schema:
             return self.app.openapi_schema
@@ -346,7 +351,7 @@ async def ping():
         self.app.include_router(mgmt_router, tags=["Liveliness/Readiness"])
 
     def add_route_dependencies(
-        self, scopes: List[Scope], dependencies=List[Depends]
+        self, scopes: list[Scope], dependencies=list[Depends]
     ) -> None:
         """Add custom dependencies to routes.
 
diff --git a/stac_fastapi/api/stac_fastapi/api/config.py b/stac_fastapi/api/stac_fastapi/api/config.py
index e6e4d882a..3918421ff 100644
--- a/stac_fastapi/api/stac_fastapi/api/config.py
+++ b/stac_fastapi/api/stac_fastapi/api/config.py
@@ -1,4 +1,5 @@
 """Application settings."""
+
 import enum
 
 
diff --git a/stac_fastapi/api/stac_fastapi/api/errors.py b/stac_fastapi/api/stac_fastapi/api/errors.py
index 3f052bd31..96c7a66a9 100644
--- a/stac_fastapi/api/stac_fastapi/api/errors.py
+++ b/stac_fastapi/api/stac_fastapi/api/errors.py
@@ -1,13 +1,14 @@
 """Error handling."""
 
 import logging
-from typing import Callable, Dict, Type, TypedDict
+from typing import Callable, Type
 
 from fastapi import FastAPI
 from fastapi.exceptions import RequestValidationError
 from starlette import status
 from starlette.requests import Request
 from starlette.responses import JSONResponse
+from typing_extensions import TypedDict
 
 from stac_fastapi.types.errors import (
     ConflictError,
@@ -67,7 +68,7 @@ def handler(request: Request, exc: Exception):
 
 
 def add_exception_handlers(
-    app: FastAPI, status_codes: Dict[Type[Exception], int]
+    app: FastAPI, status_codes: dict[Type[Exception], int]
 ) -> None:
     """Add exception handlers to the FastAPI application.
 
diff --git a/stac_fastapi/api/stac_fastapi/api/middleware.py b/stac_fastapi/api/stac_fastapi/api/middleware.py
index 3ed67d6c9..e379f5851 100644
--- a/stac_fastapi/api/stac_fastapi/api/middleware.py
+++ b/stac_fastapi/api/stac_fastapi/api/middleware.py
@@ -1,8 +1,9 @@
 """Api middleware."""
+
 import re
 import typing
 from http.client import HTTP_PORT, HTTPS_PORT
-from typing import List, Tuple
+from typing import Tuple
 
 from starlette.middleware.cors import CORSMiddleware as _CORSMiddleware
 from starlette.types import ASGIApp, Receive, Scope, Send
@@ -126,7 +127,7 @@ def _get_header_value_by_name(
     @staticmethod
     def _replace_header_value_by_name(
         scope: Scope, header_name: str, new_value: str
-    ) -> List[Tuple[str]]:
+    ) -> list[Tuple[str]]:
         return [
             (name, value)
             for name, value in scope["headers"]
diff --git a/stac_fastapi/api/stac_fastapi/api/models.py b/stac_fastapi/api/stac_fastapi/api/models.py
index 3d33b4e18..488e7b82d 100644
--- a/stac_fastapi/api/stac_fastapi/api/models.py
+++ b/stac_fastapi/api/stac_fastapi/api/models.py
@@ -4,9 +4,8 @@
 from typing import Optional, Type, Union
 
 import attr
-from fastapi import Body, Path
+from fastapi import Path
 from pydantic import BaseModel, create_model
-from pydantic.fields import UndefinedType
 
 from stac_fastapi.types.extension import ApiExtension
 from stac_fastapi.types.search import (
@@ -44,31 +43,8 @@ def create_request_model(
     # Handle POST requests
     elif all([issubclass(m, BaseModel) for m in models]):
         for model in models:
-            for k, v in model.__fields__.items():
-                field_info = v.field_info
-                body = Body(
-                    None
-                    if isinstance(field_info.default, UndefinedType)
-                    else field_info.default,
-                    default_factory=field_info.default_factory,
-                    alias=field_info.alias,
-                    alias_priority=field_info.alias_priority,
-                    title=field_info.title,
-                    description=field_info.description,
-                    const=field_info.const,
-                    gt=field_info.gt,
-                    ge=field_info.ge,
-                    lt=field_info.lt,
-                    le=field_info.le,
-                    multiple_of=field_info.multiple_of,
-                    min_items=field_info.min_items,
-                    max_items=field_info.max_items,
-                    min_length=field_info.min_length,
-                    max_length=field_info.max_length,
-                    regex=field_info.regex,
-                    extra=field_info.extra,
-                )
-                fields[k] = (v.outer_type_, body)
+            for k, field_info in model.model_fields.items():
+                fields[k] = (field_info.annotation, field_info)
         return create_model(model_name, **fields, __base__=base_model)
 
     raise TypeError("Mixed Request Model types. Check extension request types.")
diff --git a/stac_fastapi/api/stac_fastapi/api/openapi.py b/stac_fastapi/api/stac_fastapi/api/openapi.py
index a38a70bae..84d72dab1 100644
--- a/stac_fastapi/api/stac_fastapi/api/openapi.py
+++ b/stac_fastapi/api/stac_fastapi/api/openapi.py
@@ -1,4 +1,5 @@
 """openapi."""
+
 import warnings
 
 from fastapi import FastAPI
@@ -43,9 +44,9 @@ async def patched_openapi_endpoint(req: Request) -> Response:
         # Get the response from the old endpoint function
         response: JSONResponse = await old_endpoint(req)
         # Update the content type header in place
-        response.headers[
-            "content-type"
-        ] = "application/vnd.oai.openapi+json;version=3.0"
+        response.headers["content-type"] = (
+            "application/vnd.oai.openapi+json;version=3.0"
+        )
         # Return the updated response
         return response
 
diff --git a/stac_fastapi/api/stac_fastapi/api/routes.py b/stac_fastapi/api/stac_fastapi/api/routes.py
index f4eb759af..6632b9cdc 100644
--- a/stac_fastapi/api/stac_fastapi/api/routes.py
+++ b/stac_fastapi/api/stac_fastapi/api/routes.py
@@ -1,7 +1,8 @@
 """Route factories."""
+
 import functools
 import inspect
-from typing import Any, Callable, Dict, List, Optional, Type, TypedDict, Union
+from typing import Any, Callable, Optional, Type, Union
 
 from fastapi import Depends, params
 from fastapi.dependencies.utils import get_parameterless_sub_dependant
@@ -11,6 +12,7 @@
 from starlette.responses import JSONResponse, Response
 from starlette.routing import BaseRoute, Match
 from starlette.status import HTTP_204_NO_CONTENT
+from typing_extensions import TypedDict
 
 from stac_fastapi.api.models import APIRequest
 
@@ -36,7 +38,7 @@ async def run(*args, **kwargs):
 
 def create_async_endpoint(
     func: Callable,
-    request_model: Union[Type[APIRequest], Type[BaseModel], Dict],
+    request_model: Union[Type[APIRequest], Type[BaseModel], dict],
     response_class: Type[Response] = JSONResponse,
 ):
     """Wrap a function in a coroutine which may be used to create a FastAPI endpoint.
@@ -72,7 +74,7 @@ async def _endpoint(
 
         async def _endpoint(
             request: Request,
-            request_data: Dict[str, Any],  # type:ignore
+            request_data: dict[str, Any],  # type:ignore
         ):
             """Endpoint."""
             return _wrap_response(
@@ -92,7 +94,7 @@ class Scope(TypedDict, total=False):
 
 
 def add_route_dependencies(
-    routes: List[BaseRoute], scopes: List[Scope], dependencies=List[params.Depends]
+    routes: list[BaseRoute], scopes: list[Scope], dependencies=list[params.Depends]
 ) -> None:
     """Add dependencies to routes.
 
diff --git a/stac_fastapi/api/stac_fastapi/api/version.py b/stac_fastapi/api/stac_fastapi/api/version.py
index bb0c7c379..54c068f57 100644
--- a/stac_fastapi/api/stac_fastapi/api/version.py
+++ b/stac_fastapi/api/stac_fastapi/api/version.py
@@ -1,2 +1,3 @@
 """Library version."""
+
 __version__ = "2.4.9"
diff --git a/stac_fastapi/api/tests/test_api.py b/stac_fastapi/api/tests/test_api.py
index ce49cef89..9896cd4e8 100644
--- a/stac_fastapi/api/tests/test_api.py
+++ b/stac_fastapi/api/tests/test_api.py
@@ -1,4 +1,8 @@
+import json
+
+import pytest
 from fastapi import Depends, HTTPException, security, status
+from stac_pydantic import Collection, Item
 from starlette.testclient import TestClient
 
 from stac_fastapi.api.app import StacApi
@@ -41,7 +45,7 @@ def _assert_dependency_applied(api, routes):
                     method=route["method"].lower(),
                     url=path,
                     auth=("bob", "dobbs"),
-                    content='{"dummy": "payload"}',
+                    content=route.get("payload"),
                     headers={"content-type": "application/json"},
                 )
                 assert (
@@ -58,27 +62,53 @@ def test_openapi_content_type(self):
                 == "application/vnd.oai.openapi+json;version=3.0"
             )
 
-    def test_build_api_with_route_dependencies(self):
+    def test_build_api_with_route_dependencies(
+        self, collection: Collection, item: Item
+    ):
         routes = [
-            {"path": "/collections", "method": "POST"},
-            {"path": "/collections", "method": "PUT"},
+            {"path": "/collections", "method": "POST", "payload": collection},
+            {"path": "/collections", "method": "PUT", "payload": collection},
             {"path": "/collections/{collectionId}", "method": "DELETE"},
-            {"path": "/collections/{collectionId}/items", "method": "POST"},
-            {"path": "/collections/{collectionId}/items/{itemId}", "method": "PUT"},
-            {"path": "/collections/{collectionId}/items/{itemId}", "method": "DELETE"},
+            {
+                "path": "/collections/{collectionId}/items",
+                "method": "POST",
+                "payload": item,
+            },
+            {
+                "path": "/collections/{collectionId}/items/{itemId}",
+                "method": "PUT",
+                "payload": item,
+            },
+            {
+                "path": "/collections/{collectionId}/items/{itemId}",
+                "method": "DELETE",
+            },
         ]
         dependencies = [Depends(must_be_bob)]
         api = self._build_api(route_dependencies=[(routes, dependencies)])
         self._assert_dependency_applied(api, routes)
 
-    def test_add_route_dependencies_after_building_api(self):
+    def test_add_route_dependencies_after_building_api(
+        self, collection: Collection, item: Item
+    ):
         routes = [
-            {"path": "/collections", "method": "POST"},
-            {"path": "/collections", "method": "PUT"},
+            {"path": "/collections", "method": "POST", "payload": collection},
+            {"path": "/collections", "method": "PUT", "payload": collection},
             {"path": "/collections/{collectionId}", "method": "DELETE"},
-            {"path": "/collections/{collectionId}/items", "method": "POST"},
-            {"path": "/collections/{collectionId}/items/{itemId}", "method": "PUT"},
-            {"path": "/collections/{collectionId}/items/{itemId}", "method": "DELETE"},
+            {
+                "path": "/collections/{collectionId}/items",
+                "method": "POST",
+                "payload": item,
+            },
+            {
+                "path": "/collections/{collectionId}/items/{itemId}",
+                "method": "PUT",
+                "payload": item,
+            },
+            {
+                "path": "/collections/{collectionId}/items/{itemId}",
+                "method": "DELETE",
+            },
         ]
         api = self._build_api()
         api.add_route_dependencies(scopes=routes, dependencies=[Depends(must_be_bob)])
@@ -86,23 +116,17 @@ def test_add_route_dependencies_after_building_api(self):
 
 
 class DummyCoreClient(core.BaseCoreClient):
-    def all_collections(self, *args, **kwargs):
-        ...
+    def all_collections(self, *args, **kwargs): ...
 
-    def get_collection(self, *args, **kwargs):
-        ...
+    def get_collection(self, *args, **kwargs): ...
 
-    def get_item(self, *args, **kwargs):
-        ...
+    def get_item(self, *args, **kwargs): ...
 
-    def get_search(self, *args, **kwargs):
-        ...
+    def get_search(self, *args, **kwargs): ...
 
-    def post_search(self, *args, **kwargs):
-        ...
+    def post_search(self, *args, **kwargs): ...
 
-    def item_collection(self, *args, **kwargs):
-        ...
+    def item_collection(self, *args, **kwargs): ...
 
 
 class DummyTransactionsClient(core.BaseTransactionsClient):
@@ -138,3 +162,39 @@ def must_be_bob(
         detail="You're not Bob",
         headers={"WWW-Authenticate": "Basic"},
     )
+
+
+@pytest.fixture
+def collection():
+    return json.dumps(
+        {
+            "id": "test_collection",
+            "title": "Test collection",
+            "description": "This is a test collection",
+            "license": "open",
+            "keywords": [],
+            "extent": {
+                "spatial": {"bbox": [[-105, 40, -105, 40]]},
+                "temporal": {"interval": [["2023-02-12T12:00:00Z", None]]},
+            },
+            "links": [],
+        }
+    )
+
+
+@pytest.fixture
+def item():
+    return json.dumps(
+        {
+            "type": "Feature",
+            "stac_version": "1.0.0",
+            "stac_extensions": [],
+            "id": "test_item",
+            "geometry": {"type": "Point", "coordinates": [-105, 40]},
+            "bbox": [-105, 40, -105, 40],
+            "properties": {"datetime": "2023-02-12T12:00:00Z"},
+            "links": [],
+            "assets": {},
+            "collection": "test_collection",
+        }
+    )
diff --git a/stac_fastapi/extensions/setup.py b/stac_fastapi/extensions/setup.py
index a70ea5855..6b10a1ac0 100644
--- a/stac_fastapi/extensions/setup.py
+++ b/stac_fastapi/extensions/setup.py
@@ -6,10 +6,6 @@
     desc = f.read()
 
 install_requires = [
-    "attrs",
-    "pydantic[dotenv]<2",
-    "stac_pydantic==2.0.*",
-    "stac-fastapi.types",
     "stac-fastapi.api",
 ]
 
@@ -30,12 +26,12 @@
     description="An implementation of STAC API based on the FastAPI framework.",
     long_description=desc,
     long_description_content_type="text/markdown",
-    python_requires=">=3.8",
+    python_requires=">=3.9",
     classifiers=[
         "Intended Audience :: Developers",
         "Intended Audience :: Information Technology",
         "Intended Audience :: Science/Research",
-        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
         "License :: OSI Approved :: MIT License",
     ],
     keywords="STAC FastAPI COG",
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/__init__.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/__init__.py
index 96317fe4a..74f15ed0a 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/__init__.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/__init__.py
@@ -1,4 +1,5 @@
 """stac_api.extensions.core module."""
+
 from .context import ContextExtension
 from .fields import FieldsExtension
 from .filter import FilterExtension
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/context.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/context.py
index 90faae914..58ec39d4a 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/context.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/context.py
@@ -1,5 +1,6 @@
 """Context extension."""
-from typing import List, Optional
+
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -17,7 +18,7 @@ class ContextExtension(ApiExtension):
     https://github.com/stac-api-extensions/context
     """
 
-    conformance_classes: List[str] = attr.ib(
+    conformance_classes: list[str] = attr.ib(
         factory=lambda: ["https://api.stacspec.org/v1.0.0-rc.2/item-search#context"]
     )
     schema_href: Optional[str] = attr.ib(
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/__init__.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/__init__.py
index b9a246b63..087d01b7a 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/__init__.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/__init__.py
@@ -1,6 +1,5 @@
 """Fields extension module."""
 
-
 from .fields import FieldsExtension
 
 __all__ = ["FieldsExtension"]
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/fields.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/fields.py
index df4cd44de..39b62f227 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/fields.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/fields.py
@@ -1,5 +1,6 @@
 """Fields extension."""
-from typing import List, Optional, Set
+
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -31,10 +32,10 @@ class FieldsExtension(ApiExtension):
     GET = FieldsExtensionGetRequest
     POST = FieldsExtensionPostRequest
 
-    conformance_classes: List[str] = attr.ib(
+    conformance_classes: list[str] = attr.ib(
         factory=lambda: ["https://api.stacspec.org/v1.0.0/item-search#fields"]
     )
-    default_includes: Set[str] = attr.ib(
+    default_includes: set[str] = attr.ib(
         factory=lambda: {
             "id",
             "type",
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/request.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/request.py
index 4cfbd3293..903f10595 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/request.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/fields/request.py
@@ -1,6 +1,6 @@
 """Request models for the fields extension."""
 
-from typing import Dict, Optional, Set
+from typing import Optional
 
 import attr
 from pydantic import BaseModel, Field
@@ -17,11 +17,11 @@ class PostFieldsExtension(BaseModel):
         exclude: set of fields to exclude.
     """
 
-    include: Optional[Set[str]] = set()
-    exclude: Optional[Set[str]] = set()
+    include: Optional[set[str]] = set()
+    exclude: Optional[set[str]] = set()
 
     @staticmethod
-    def _get_field_dict(fields: Optional[Set[str]]) -> Dict:
+    def _get_field_dict(fields: Optional[set[str]]) -> dict:
         """Pydantic include/excludes notation.
 
         Internal method to create a dictionary for advanced include or exclude
@@ -42,7 +42,7 @@ def _get_field_dict(fields: Optional[Set[str]]) -> Dict:
         return field_dict
 
     @property
-    def filter_fields(self) -> Dict:
+    def filter_fields(self) -> dict:
         """Create pydantic include/exclude expression.
 
         Create dictionary of fields to include/exclude on model export based on
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/__init__.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/__init__.py
index 78256bfd2..256f3e06e 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/__init__.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/__init__.py
@@ -1,6 +1,5 @@
 """Filter extension module."""
 
-
 from .filter import FilterExtension
 
 __all__ = ["FilterExtension"]
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/filter.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/filter.py
index 2f875907a..878f1cd74 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/filter.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/filter.py
@@ -1,7 +1,7 @@
 # encoding: utf-8
 """Filter Extension."""
 from enum import Enum
-from typing import List, Type, Union
+from typing import Type, Union
 
 import attr
 from fastapi import APIRouter, FastAPI
@@ -70,7 +70,7 @@ class FilterExtension(ApiExtension):
     client: Union[AsyncBaseFiltersClient, BaseFiltersClient] = attr.ib(
         factory=BaseFiltersClient
     )
-    conformance_classes: List[str] = attr.ib(
+    conformance_classes: list[str] = attr.ib(
         default=[
             FilterConformanceClasses.FILTER,
             FilterConformanceClasses.FEATURES_FILTER,
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/request.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/request.py
index 1fcd6b0b9..fd7f029de 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/request.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/filter/request.py
@@ -1,7 +1,7 @@
 """Filter extension request models."""
 
 from enum import Enum
-from typing import Any, Dict, Optional
+from typing import Any, Optional
 
 import attr
 from pydantic import BaseModel, Field
@@ -36,6 +36,6 @@ class FilterExtensionGetRequest(APIRequest):
 class FilterExtensionPostRequest(BaseModel):
     """Filter extension POST request model."""
 
-    filter: Optional[Dict[str, Any]] = None
+    filter: Optional[dict[str, Any]] = None
     filter_crs: Optional[str] = Field(alias="filter-crs", default=None)
     filter_lang: Optional[FilterLang] = Field(alias="filter-lang", default="cql-json")
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/pagination.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/pagination.py
index 296e9ae6a..c7fdf19c2 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/pagination.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/pagination.py
@@ -1,6 +1,6 @@
 """Pagination API extension."""
 
-from typing import List, Optional
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -22,7 +22,7 @@ class PaginationExtension(ApiExtension):
     GET = GETPagination
     POST = POSTPagination
 
-    conformance_classes: List[str] = attr.ib(factory=list)
+    conformance_classes: list[str] = attr.ib(factory=list)
     schema_href: Optional[str] = attr.ib(default=None)
 
     def register(self, app: FastAPI) -> None:
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/token_pagination.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/token_pagination.py
index d3fa10391..c8b0ef3ed 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/token_pagination.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/pagination/token_pagination.py
@@ -1,6 +1,6 @@
 """Token pagination API extension."""
 
-from typing import List, Optional
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -22,7 +22,7 @@ class TokenPaginationExtension(ApiExtension):
     GET = GETTokenPagination
     POST = POSTTokenPagination
 
-    conformance_classes: List[str] = attr.ib(factory=list)
+    conformance_classes: list[str] = attr.ib(factory=list)
     schema_href: Optional[str] = attr.ib(default=None)
 
     def register(self, app: FastAPI) -> None:
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/query/query.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/query/query.py
index 3e85b406d..f70d9b056 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/query/query.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/query/query.py
@@ -1,5 +1,6 @@
 """Query extension."""
-from typing import List, Optional
+
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -22,7 +23,7 @@ class QueryExtension(ApiExtension):
     GET = QueryExtensionGetRequest
     POST = QueryExtensionPostRequest
 
-    conformance_classes: List[str] = attr.ib(
+    conformance_classes: list[str] = attr.ib(
         factory=lambda: ["https://api.stacspec.org/v1.0.0/item-search#query"]
     )
     schema_href: Optional[str] = attr.ib(default=None)
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/query/request.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/query/request.py
index 8b282884a..867b7fc57 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/query/request.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/query/request.py
@@ -1,6 +1,6 @@
 """Request model for the Query extension."""
 
-from typing import Any, Dict, Optional
+from typing import Any, Optional
 
 import attr
 from pydantic import BaseModel
@@ -18,4 +18,4 @@ class QueryExtensionGetRequest(APIRequest):
 class QueryExtensionPostRequest(BaseModel):
     """Query Extension POST request model."""
 
-    query: Optional[Dict[str, Dict[str, Any]]]
+    query: Optional[dict[str, dict[str, Any]]] = None
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/request.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/request.py
index c19f40dba..5ab523e25 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/request.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/request.py
@@ -1,7 +1,7 @@
 # encoding: utf-8
 """Request model for the Sort Extension."""
 
-from typing import List, Optional
+from typing import Optional
 
 import attr
 from pydantic import BaseModel
@@ -20,4 +20,4 @@ class SortExtensionGetRequest(APIRequest):
 class SortExtensionPostRequest(BaseModel):
     """Sortby parameter for POST requests."""
 
-    sortby: Optional[List[PostSortModel]]
+    sortby: Optional[list[PostSortModel]] = None
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/sort.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/sort.py
index 5dd96cfa6..35b616658 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/sort.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/sort/sort.py
@@ -1,5 +1,6 @@
 """Sort extension."""
-from typing import List, Optional
+
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -21,7 +22,7 @@ class SortExtension(ApiExtension):
     GET = SortExtensionGetRequest
     POST = SortExtensionPostRequest
 
-    conformance_classes: List[str] = attr.ib(
+    conformance_classes: list[str] = attr.ib(
         factory=lambda: ["https://api.stacspec.org/v1.0.0/item-search#sort"]
     )
     schema_href: Optional[str] = attr.ib(default=None)
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/core/transaction.py b/stac_fastapi/extensions/stac_fastapi/extensions/core/transaction.py
index 480ff09b5..5932e5270 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/core/transaction.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/core/transaction.py
@@ -1,14 +1,14 @@
 """Transaction extension."""
-from typing import List, Optional, Type, Union
+
+from typing import Optional, Type, Union
 
 import attr
 from fastapi import APIRouter, Body, FastAPI
-from stac_pydantic import Collection, Item
+from stac_pydantic import Collection, Item, ItemCollection
 from starlette.responses import JSONResponse, Response
 
 from stac_fastapi.api.models import CollectionUri, ItemUri
 from stac_fastapi.api.routes import create_async_endpoint
-from stac_fastapi.types import stac as stac_types
 from stac_fastapi.types.config import ApiSettings
 from stac_fastapi.types.core import AsyncBaseTransactionsClient, BaseTransactionsClient
 from stac_fastapi.types.extension import ApiExtension
@@ -18,16 +18,14 @@
 class PostItem(CollectionUri):
     """Create Item."""
 
-    item: Union[stac_types.Item, stac_types.ItemCollection] = attr.ib(
-        default=Body(None)
-    )
+    item: Union[Item, ItemCollection] = attr.ib(default=Body(None))
 
 
 @attr.s
 class PutItem(ItemUri):
     """Update Item."""
 
-    item: stac_types.Item = attr.ib(default=Body(None))
+    item: Item = attr.ib(default=Body(None))
 
 
 @attr.s
@@ -51,7 +49,7 @@ class TransactionExtension(ApiExtension):
 
     client: Union[AsyncBaseTransactionsClient, BaseTransactionsClient] = attr.ib()
     settings: ApiSettings = attr.ib()
-    conformance_classes: List[str] = attr.ib(
+    conformance_classes: list[str] = attr.ib(
         factory=lambda: [
             "https://api.stacspec.org/v1.0.0-rc.3/ogcapi-features/extensions/transaction",
         ]
@@ -111,9 +109,7 @@ def register_create_collection(self):
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
             methods=["POST"],
-            endpoint=create_async_endpoint(
-                self.client.create_collection, stac_types.Collection
-            ),
+            endpoint=create_async_endpoint(self.client.create_collection, Collection),
         )
 
     def register_update_collection(self):
@@ -126,9 +122,7 @@ def register_update_collection(self):
             response_model_exclude_unset=True,
             response_model_exclude_none=True,
             methods=["PUT"],
-            endpoint=create_async_endpoint(
-                self.client.update_collection, stac_types.Collection
-            ),
+            endpoint=create_async_endpoint(self.client.update_collection, Collection),
         )
 
     def register_delete_collection(self):
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/third_party/__init__.py b/stac_fastapi/extensions/stac_fastapi/extensions/third_party/__init__.py
index ab7349e60..d35c4c8f9 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/third_party/__init__.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/third_party/__init__.py
@@ -1,4 +1,5 @@
 """stac_api.extensions.third_party module."""
+
 from .bulk_transactions import BulkTransactionExtension
 
 __all__ = ("BulkTransactionExtension",)
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/third_party/bulk_transactions.py b/stac_fastapi/extensions/stac_fastapi/extensions/third_party/bulk_transactions.py
index 9fa96ff2b..e326649ab 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/third_party/bulk_transactions.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/third_party/bulk_transactions.py
@@ -1,7 +1,8 @@
 """Bulk transactions extension."""
+
 import abc
 from enum import Enum
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Optional, Union
 
 import attr
 from fastapi import APIRouter, FastAPI
@@ -22,7 +23,7 @@ class BulkTransactionMethod(str, Enum):
 class Items(BaseModel):
     """A group of STAC Item objects, in the form of a dictionary from Item.id -> Item."""
 
-    items: Dict[str, Any]
+    items: dict[str, Any]
     method: BulkTransactionMethod = BulkTransactionMethod.INSERT
 
     def __iter__(self):
@@ -109,10 +110,10 @@ class BulkTransactionExtension(ApiExtension):
         }
     """
 
-    client: Union[
-        AsyncBaseBulkTransactionsClient, BaseBulkTransactionsClient
-    ] = attr.ib()
-    conformance_classes: List[str] = attr.ib(default=list())
+    client: Union[AsyncBaseBulkTransactionsClient, BaseBulkTransactionsClient] = (
+        attr.ib()
+    )
+    conformance_classes: list[str] = attr.ib(default=list())
     schema_href: Optional[str] = attr.ib(default=None)
 
     def register(self, app: FastAPI) -> None:
diff --git a/stac_fastapi/extensions/stac_fastapi/extensions/version.py b/stac_fastapi/extensions/stac_fastapi/extensions/version.py
index bb0c7c379..54c068f57 100644
--- a/stac_fastapi/extensions/stac_fastapi/extensions/version.py
+++ b/stac_fastapi/extensions/stac_fastapi/extensions/version.py
@@ -1,2 +1,3 @@
 """Library version."""
+
 __version__ = "2.4.9"
diff --git a/stac_fastapi/extensions/tests/test_transaction.py b/stac_fastapi/extensions/tests/test_transaction.py
index fc5acc2cf..b2f59ae47 100644
--- a/stac_fastapi/extensions/tests/test_transaction.py
+++ b/stac_fastapi/extensions/tests/test_transaction.py
@@ -2,13 +2,14 @@
 from typing import Iterator, Union
 
 import pytest
+from stac_pydantic.item import Item
+from stac_pydantic.item_collection import ItemCollection
 from starlette.testclient import TestClient
 
 from stac_fastapi.api.app import StacApi
 from stac_fastapi.extensions.core import TransactionExtension
 from stac_fastapi.types.config import ApiSettings
 from stac_fastapi.types.core import BaseCoreClient, BaseTransactionsClient
-from stac_fastapi.types.stac import Item, ItemCollection
 
 
 class DummyCoreClient(BaseCoreClient):
@@ -35,7 +36,7 @@ class DummyTransactionsClient(BaseTransactionsClient):
     """Defines a pattern for implementing the STAC transaction extension."""
 
     def create_item(self, item: Union[Item, ItemCollection], *args, **kwargs):
-        return {"created": True, "type": item["type"]}
+        return {"created": True, "type": item.type}
 
     def update_item(self, *args, **kwargs):
         raise NotImplementedError
@@ -114,7 +115,7 @@ def item() -> Item:
         "id": "test_item",
         "geometry": {"type": "Point", "coordinates": [-105, 40]},
         "bbox": [-105, 40, -105, 40],
-        "properties": {},
+        "properties": {"datetime": "2023-02-12T12:00:00Z"},
         "links": [],
         "assets": {},
         "collection": "test_collection",
diff --git a/stac_fastapi/types/setup.py b/stac_fastapi/types/setup.py
index 9a06fda95..4cee32145 100644
--- a/stac_fastapi/types/setup.py
+++ b/stac_fastapi/types/setup.py
@@ -6,12 +6,13 @@
     desc = f.read()
 
 install_requires = [
-    "fastapi>=0.73.0",
+    "fastapi>=0.109.0",
     "attrs",
-    "pydantic[dotenv]<2",
-    "stac_pydantic==2.0.*",
-    "pystac==1.*",
+    "pydantic<3",
+    "stac_pydantic==3.0.*",
+    "pystac[validation]==1.*",
     "iso8601>=1.0.2,<2.2.0",
+    "pydantic-settings==2.1.0",
 ]
 
 extra_reqs = {
@@ -31,12 +32,12 @@
     description="An implementation of STAC API based on the FastAPI framework.",
     long_description=desc,
     long_description_content_type="text/markdown",
-    python_requires=">=3.8",
+    python_requires=">=3.9",
     classifiers=[
         "Intended Audience :: Developers",
         "Intended Audience :: Information Technology",
         "Intended Audience :: Science/Research",
-        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
         "License :: OSI Approved :: MIT License",
     ],
     keywords="STAC FastAPI COG",
diff --git a/stac_fastapi/types/stac_fastapi/types/config.py b/stac_fastapi/types/stac_fastapi/types/config.py
index b3f22fb65..9a0622c58 100644
--- a/stac_fastapi/types/stac_fastapi/types/config.py
+++ b/stac_fastapi/types/stac_fastapi/types/config.py
@@ -1,7 +1,8 @@
 """stac_fastapi.types.config module."""
-from typing import Optional, Set
 
-from pydantic import BaseSettings
+from typing import Optional
+
+from pydantic_settings import BaseSettings, SettingsConfigDict
 
 
 class ApiSettings(BaseSettings):
@@ -20,7 +21,7 @@ class ApiSettings(BaseSettings):
 
     # TODO: Remove `default_includes` attribute so we can use
     # `pydantic.BaseSettings` instead
-    default_includes: Optional[Set[str]] = None
+    default_includes: Optional[set[str]] = None
 
     app_host: str = "0.0.0.0"
     app_port: int = 8000
@@ -29,12 +30,7 @@ class ApiSettings(BaseSettings):
 
     openapi_url: str = "/api"
     docs_url: str = "/api.html"
-
-    class Config:
-        """Model config (https://pydantic-docs.helpmanual.io/usage/model_config/)."""
-
-        extra = "allow"
-        env_file = ".env"
+    model_config = SettingsConfigDict(extra="allow", env_file=".env")
 
 
 class Settings:
diff --git a/stac_fastapi/types/stac_fastapi/types/conformance.py b/stac_fastapi/types/stac_fastapi/types/conformance.py
index 13836aaf5..840584c1b 100644
--- a/stac_fastapi/types/stac_fastapi/types/conformance.py
+++ b/stac_fastapi/types/stac_fastapi/types/conformance.py
@@ -1,4 +1,5 @@
 """Conformance Classes."""
+
 from enum import Enum
 
 
diff --git a/stac_fastapi/types/stac_fastapi/types/core.py b/stac_fastapi/types/stac_fastapi/types/core.py
index 5798de968..72921f682 100644
--- a/stac_fastapi/types/stac_fastapi/types/core.py
+++ b/stac_fastapi/types/stac_fastapi/types/core.py
@@ -1,25 +1,25 @@
 """Base clients."""
+
 import abc
 from datetime import datetime
-from typing import Any, Dict, List, Optional, Union
+from typing import Any, Optional, Union
 from urllib.parse import urljoin
 
 import attr
 from fastapi import Request
+from stac_pydantic import Collection, Item, ItemCollection, api
 from stac_pydantic.links import Relations
 from stac_pydantic.shared import MimeTypes
 from stac_pydantic.version import STAC_VERSION
 from starlette.responses import Response
 
-from stac_fastapi.types import stac as stac_types
 from stac_fastapi.types.conformance import BASE_CONFORMANCE_CLASSES
 from stac_fastapi.types.extension import ApiExtension
 from stac_fastapi.types.requests import get_base_url
 from stac_fastapi.types.search import BaseSearchPostRequest
-from stac_fastapi.types.stac import Conformance
 
 NumType = Union[float, int]
-StacType = Dict[str, Any]
+StacType = dict[str, Any]
 
 
 @attr.s  # type:ignore
@@ -30,9 +30,9 @@ class BaseTransactionsClient(abc.ABC):
     def create_item(
         self,
         collection_id: str,
-        item: Union[stac_types.Item, stac_types.ItemCollection],
+        item: Union[Item, ItemCollection],
         **kwargs,
-    ) -> Optional[Union[stac_types.Item, Response, None]]:
+    ) -> Optional[Union[Item, Response, None]]:
         """Create a new item.
 
         Called with `POST /collections/{collection_id}/items`.
@@ -48,8 +48,8 @@ def create_item(
 
     @abc.abstractmethod
     def update_item(
-        self, collection_id: str, item_id: str, item: stac_types.Item, **kwargs
-    ) -> Optional[Union[stac_types.Item, Response]]:
+        self, collection_id: str, item_id: str, item: Item, **kwargs
+    ) -> Optional[Union[Item, Response]]:
         """Perform a complete update on an existing item.
 
         Called with `PUT /collections/{collection_id}/items`. It is expected
@@ -69,7 +69,7 @@ def update_item(
     @abc.abstractmethod
     def delete_item(
         self, item_id: str, collection_id: str, **kwargs
-    ) -> Optional[Union[stac_types.Item, Response]]:
+    ) -> Optional[Union[Item, Response]]:
         """Delete an item from a collection.
 
         Called with `DELETE /collections/{collection_id}/items/{item_id}`
@@ -85,8 +85,8 @@ def delete_item(
 
     @abc.abstractmethod
     def create_collection(
-        self, collection: stac_types.Collection, **kwargs
-    ) -> Optional[Union[stac_types.Collection, Response]]:
+        self, collection: Collection, **kwargs
+    ) -> Optional[Union[Collection, Response]]:
         """Create a new collection.
 
         Called with `POST /collections`.
@@ -101,8 +101,8 @@ def create_collection(
 
     @abc.abstractmethod
     def update_collection(
-        self, collection: stac_types.Collection, **kwargs
-    ) -> Optional[Union[stac_types.Collection, Response]]:
+        self, collection: Collection, **kwargs
+    ) -> Optional[Union[Collection, Response]]:
         """Perform a complete update on an existing collection.
 
         Called with `PUT /collections`. It is expected that this item already
@@ -122,7 +122,7 @@ def update_collection(
     @abc.abstractmethod
     def delete_collection(
         self, collection_id: str, **kwargs
-    ) -> Optional[Union[stac_types.Collection, Response]]:
+    ) -> Optional[Union[Collection, Response]]:
         """Delete a collection.
 
         Called with `DELETE /collections/{collection_id}`
@@ -144,9 +144,9 @@ class AsyncBaseTransactionsClient(abc.ABC):
     async def create_item(
         self,
         collection_id: str,
-        item: Union[stac_types.Item, stac_types.ItemCollection],
+        item: Union[Item, ItemCollection],
         **kwargs,
-    ) -> Optional[Union[stac_types.Item, Response, None]]:
+    ) -> Optional[Union[Item, Response, None]]:
         """Create a new item.
 
         Called with `POST /collections/{collection_id}/items`.
@@ -162,8 +162,8 @@ async def create_item(
 
     @abc.abstractmethod
     async def update_item(
-        self, collection_id: str, item_id: str, item: stac_types.Item, **kwargs
-    ) -> Optional[Union[stac_types.Item, Response]]:
+        self, collection_id: str, item_id: str, item: Item, **kwargs
+    ) -> Optional[Union[Item, Response]]:
         """Perform a complete update on an existing item.
 
         Called with `PUT /collections/{collection_id}/items`. It is expected
@@ -182,7 +182,7 @@ async def update_item(
     @abc.abstractmethod
     async def delete_item(
         self, item_id: str, collection_id: str, **kwargs
-    ) -> Optional[Union[stac_types.Item, Response]]:
+    ) -> Optional[Union[Item, Response]]:
         """Delete an item from a collection.
 
         Called with `DELETE /collections/{collection_id}/items/{item_id}`
@@ -198,8 +198,8 @@ async def delete_item(
 
     @abc.abstractmethod
     async def create_collection(
-        self, collection: stac_types.Collection, **kwargs
-    ) -> Optional[Union[stac_types.Collection, Response]]:
+        self, collection: Collection, **kwargs
+    ) -> Optional[Union[Collection, Response]]:
         """Create a new collection.
 
         Called with `POST /collections`.
@@ -214,8 +214,8 @@ async def create_collection(
 
     @abc.abstractmethod
     async def update_collection(
-        self, collection: stac_types.Collection, **kwargs
-    ) -> Optional[Union[stac_types.Collection, Response]]:
+        self, collection: Collection, **kwargs
+    ) -> Optional[Union[Collection, Response]]:
         """Perform a complete update on an existing collection.
 
         Called with `PUT /collections`. It is expected that this item already
@@ -234,7 +234,7 @@ async def update_collection(
     @abc.abstractmethod
     async def delete_collection(
         self, collection_id: str, **kwargs
-    ) -> Optional[Union[stac_types.Collection, Response]]:
+    ) -> Optional[Union[Collection, Response]]:
         """Delete a collection.
 
         Called with `DELETE /collections/{collection_id}`
@@ -260,10 +260,10 @@ class LandingPageMixin(abc.ABC):
     def _landing_page(
         self,
         base_url: str,
-        conformance_classes: List[str],
-        extension_schemas: List[str],
-    ) -> stac_types.LandingPage:
-        landing_page = stac_types.LandingPage(
+        conformance_classes: list[str],
+        extension_schemas: list[str],
+    ) -> api.LandingPage:
+        landing_page = api.LandingPage(
             type="Catalog",
             id=self.landing_page_id,
             title=self.title,
@@ -320,13 +320,13 @@ class BaseCoreClient(LandingPageMixin, abc.ABC):
         extensions: list of registered api extensions.
     """
 
-    base_conformance_classes: List[str] = attr.ib(
+    base_conformance_classes: list[str] = attr.ib(
         factory=lambda: BASE_CONFORMANCE_CLASSES
     )
-    extensions: List[ApiExtension] = attr.ib(default=attr.Factory(list))
+    extensions: list[ApiExtension] = attr.ib(default=attr.Factory(list))
     post_request_model = attr.ib(default=BaseSearchPostRequest)
 
-    def conformance_classes(self) -> List[str]:
+    def conformance_classes(self) -> list[str]:
         """Generate conformance classes by adding extension conformance to base
         conformance classes."""
         base_conformance_classes = self.base_conformance_classes.copy()
@@ -351,7 +351,7 @@ def list_conformance_classes(self):
 
         return base_conformance
 
-    def landing_page(self, **kwargs) -> stac_types.LandingPage:
+    def landing_page(self, **kwargs) -> api.LandingPage:
         """Landing page.
 
         Called with `GET /`.
@@ -405,7 +405,7 @@ def landing_page(self, **kwargs) -> stac_types.LandingPage:
 
         return landing_page
 
-    def conformance(self, **kwargs) -> stac_types.Conformance:
+    def conformance(self, **kwargs) -> api.ConformanceClasses:
         """Conformance classes.
 
         Called with `GET /conformance`.
@@ -413,12 +413,12 @@ def conformance(self, **kwargs) -> stac_types.Conformance:
         Returns:
             Conformance classes which the server conforms to.
         """
-        return Conformance(conformsTo=self.conformance_classes())
+        return api.ConformanceClasses(conformsTo=self.conformance_classes())
 
     @abc.abstractmethod
     def post_search(
         self, search_request: BaseSearchPostRequest, **kwargs
-    ) -> stac_types.ItemCollection:
+    ) -> api.ItemCollection:
         """Cross catalog search (POST).
 
         Called with `POST /search`.
@@ -434,18 +434,18 @@ def post_search(
     @abc.abstractmethod
     def get_search(
         self,
-        collections: Optional[List[str]] = None,
-        ids: Optional[List[str]] = None,
-        bbox: Optional[List[NumType]] = None,
+        collections: Optional[list[str]] = None,
+        ids: Optional[list[str]] = None,
+        bbox: Optional[list[NumType]] = None,
         datetime: Optional[Union[str, datetime]] = None,
         limit: Optional[int] = 10,
         query: Optional[str] = None,
         token: Optional[str] = None,
-        fields: Optional[List[str]] = None,
+        fields: Optional[list[str]] = None,
         sortby: Optional[str] = None,
         intersects: Optional[str] = None,
         **kwargs,
-    ) -> stac_types.ItemCollection:
+    ) -> api.ItemCollection:
         """Cross catalog search (GET).
 
         Called with `GET /search`.
@@ -456,7 +456,7 @@ def get_search(
         ...
 
     @abc.abstractmethod
-    def get_item(self, item_id: str, collection_id: str, **kwargs) -> stac_types.Item:
+    def get_item(self, item_id: str, collection_id: str, **kwargs) -> api.Item:
         """Get item by id.
 
         Called with `GET /collections/{collection_id}/items/{item_id}`.
@@ -471,7 +471,7 @@ def get_item(self, item_id: str, collection_id: str, **kwargs) -> stac_types.Ite
         ...
 
     @abc.abstractmethod
-    def all_collections(self, **kwargs) -> stac_types.Collections:
+    def all_collections(self, **kwargs) -> api.Collections:
         """Get all available collections.
 
         Called with `GET /collections`.
@@ -482,7 +482,7 @@ def all_collections(self, **kwargs) -> stac_types.Collections:
         ...
 
     @abc.abstractmethod
-    def get_collection(self, collection_id: str, **kwargs) -> stac_types.Collection:
+    def get_collection(self, collection_id: str, **kwargs) -> api.Collection:
         """Get collection by id.
 
         Called with `GET /collections/{collection_id}`.
@@ -499,12 +499,12 @@ def get_collection(self, collection_id: str, **kwargs) -> stac_types.Collection:
     def item_collection(
         self,
         collection_id: str,
-        bbox: Optional[List[NumType]] = None,
+        bbox: Optional[list[NumType]] = None,
         datetime: Optional[Union[str, datetime]] = None,
         limit: int = 10,
         token: str = None,
         **kwargs,
-    ) -> stac_types.ItemCollection:
+    ) -> api.ItemCollection:
         """Get all items from a specific collection.
 
         Called with `GET /collections/{collection_id}/items`
@@ -528,13 +528,13 @@ class AsyncBaseCoreClient(LandingPageMixin, abc.ABC):
         extensions: list of registered api extensions.
     """
 
-    base_conformance_classes: List[str] = attr.ib(
+    base_conformance_classes: list[str] = attr.ib(
         factory=lambda: BASE_CONFORMANCE_CLASSES
     )
-    extensions: List[ApiExtension] = attr.ib(default=attr.Factory(list))
+    extensions: list[ApiExtension] = attr.ib(default=attr.Factory(list))
     post_request_model = attr.ib(default=BaseSearchPostRequest)
 
-    def conformance_classes(self) -> List[str]:
+    def conformance_classes(self) -> list[str]:
         """Generate conformance classes by adding extension conformance to base
         conformance classes."""
         conformance_classes = self.base_conformance_classes.copy()
@@ -549,7 +549,7 @@ def extension_is_enabled(self, extension: str) -> bool:
         """Check if an api extension is enabled."""
         return any([type(ext).__name__ == extension for ext in self.extensions])
 
-    async def landing_page(self, **kwargs) -> stac_types.LandingPage:
+    async def landing_page(self, **kwargs) -> api.LandingPage:
         """Landing page.
 
         Called with `GET /`.
@@ -601,7 +601,7 @@ async def landing_page(self, **kwargs) -> stac_types.LandingPage:
 
         return landing_page
 
-    async def conformance(self, **kwargs) -> stac_types.Conformance:
+    async def conformance(self, **kwargs) -> api.ConformanceClasses:
         """Conformance classes.
 
         Called with `GET /conformance`.
@@ -609,12 +609,12 @@ async def conformance(self, **kwargs) -> stac_types.Conformance:
         Returns:
             Conformance classes which the server conforms to.
         """
-        return Conformance(conformsTo=self.conformance_classes())
+        return api.ConformanceClasses(conformsTo=self.conformance_classes())
 
     @abc.abstractmethod
     async def post_search(
         self, search_request: BaseSearchPostRequest, **kwargs
-    ) -> stac_types.ItemCollection:
+    ) -> api.ItemCollection:
         """Cross catalog search (POST).
 
         Called with `POST /search`.
@@ -630,18 +630,18 @@ async def post_search(
     @abc.abstractmethod
     async def get_search(
         self,
-        collections: Optional[List[str]] = None,
-        ids: Optional[List[str]] = None,
-        bbox: Optional[List[NumType]] = None,
+        collections: Optional[list[str]] = None,
+        ids: Optional[list[str]] = None,
+        bbox: Optional[list[NumType]] = None,
         datetime: Optional[Union[str, datetime]] = None,
         limit: Optional[int] = 10,
         query: Optional[str] = None,
         token: Optional[str] = None,
-        fields: Optional[List[str]] = None,
+        fields: Optional[list[str]] = None,
         sortby: Optional[str] = None,
         intersects: Optional[str] = None,
         **kwargs,
-    ) -> stac_types.ItemCollection:
+    ) -> api.ItemCollection:
         """Cross catalog search (GET).
 
         Called with `GET /search`.
@@ -652,9 +652,7 @@ async def get_search(
         ...
 
     @abc.abstractmethod
-    async def get_item(
-        self, item_id: str, collection_id: str, **kwargs
-    ) -> stac_types.Item:
+    async def get_item(self, item_id: str, collection_id: str, **kwargs) -> api.Item:
         """Get item by id.
 
         Called with `GET /collections/{collection_id}/items/{item_id}`.
@@ -669,7 +667,7 @@ async def get_item(
         ...
 
     @abc.abstractmethod
-    async def all_collections(self, **kwargs) -> stac_types.Collections:
+    async def all_collections(self, **kwargs) -> api.Collections:
         """Get all available collections.
 
         Called with `GET /collections`.
@@ -680,9 +678,7 @@ async def all_collections(self, **kwargs) -> stac_types.Collections:
         ...
 
     @abc.abstractmethod
-    async def get_collection(
-        self, collection_id: str, **kwargs
-    ) -> stac_types.Collection:
+    async def get_collection(self, collection_id: str, **kwargs) -> api.Collection:
         """Get collection by id.
 
         Called with `GET /collections/{collection_id}`.
@@ -699,12 +695,12 @@ async def get_collection(
     async def item_collection(
         self,
         collection_id: str,
-        bbox: Optional[List[NumType]] = None,
+        bbox: Optional[list[NumType]] = None,
         datetime: Optional[Union[str, datetime]] = None,
         limit: int = 10,
         token: str = None,
         **kwargs,
-    ) -> stac_types.ItemCollection:
+    ) -> api.ItemCollection:
         """Get all items from a specific collection.
 
         Called with `GET /collections/{collection_id}/items`
@@ -726,7 +722,7 @@ class AsyncBaseFiltersClient(abc.ABC):
 
     async def get_queryables(
         self, collection_id: Optional[str] = None, **kwargs
-    ) -> Dict[str, Any]:
+    ) -> dict[str, Any]:
         """Get the queryables available for the given collection_id.
 
         If collection_id is None, returns the intersection of all queryables over all
@@ -752,7 +748,7 @@ class BaseFiltersClient(abc.ABC):
 
     def get_queryables(
         self, collection_id: Optional[str] = None, **kwargs
-    ) -> Dict[str, Any]:
+    ) -> dict[str, Any]:
         """Get the queryables available for the given collection_id.
 
         If collection_id is None, returns the intersection of all queryables over all
diff --git a/stac_fastapi/types/stac_fastapi/types/extension.py b/stac_fastapi/types/stac_fastapi/types/extension.py
index 732a907bf..11b5138f7 100644
--- a/stac_fastapi/types/stac_fastapi/types/extension.py
+++ b/stac_fastapi/types/stac_fastapi/types/extension.py
@@ -1,6 +1,7 @@
 """Base api extension."""
+
 import abc
-from typing import List, Optional
+from typing import Optional
 
 import attr
 from fastapi import FastAPI
@@ -21,7 +22,7 @@ def get_request_model(self, verb: Optional[str] = "GET") -> Optional[BaseModel]:
         """
         return getattr(self, verb)
 
-    conformance_classes: List[str] = attr.ib(factory=list)
+    conformance_classes: list[str] = attr.ib(factory=list)
     schema_href: Optional[str] = attr.ib(default=None)
 
     @abc.abstractmethod
diff --git a/stac_fastapi/types/stac_fastapi/types/links.py b/stac_fastapi/types/stac_fastapi/types/links.py
index 2a4c954d0..52b99ecb6 100644
--- a/stac_fastapi/types/stac_fastapi/types/links.py
+++ b/stac_fastapi/types/stac_fastapi/types/links.py
@@ -1,6 +1,6 @@
 """Link helpers."""
 
-from typing import Any, Dict, List
+from typing import Any
 from urllib.parse import urljoin
 
 import attr
@@ -13,12 +13,12 @@
 INFERRED_LINK_RELS = ["self", "item", "parent", "collection", "root"]
 
 
-def filter_links(links: List[Dict]) -> List[Dict]:
+def filter_links(links: list[dict]) -> list[dict]:
     """Remove inferred links."""
     return [link for link in links if link["rel"] not in INFERRED_LINK_RELS]
 
 
-def resolve_links(links: list, base_url: str) -> List[Dict]:
+def resolve_links(links: list, base_url: str) -> list[dict]:
     """Convert relative links to absolute links."""
     filtered_links = filter_links(links)
     for link in filtered_links:
@@ -33,7 +33,7 @@ class BaseLinks:
     collection_id: str = attr.ib()
     base_url: str = attr.ib()
 
-    def root(self) -> Dict[str, Any]:
+    def root(self) -> dict[str, Any]:
         """Return the catalog root."""
         return dict(rel=Relations.root, type=MimeTypes.json, href=self.base_url)
 
@@ -42,7 +42,7 @@ def root(self) -> Dict[str, Any]:
 class CollectionLinks(BaseLinks):
     """Create inferred links specific to collections."""
 
-    def self(self) -> Dict[str, Any]:
+    def self(self) -> dict[str, Any]:
         """Create the `self` link."""
         return dict(
             rel=Relations.self,
@@ -50,11 +50,11 @@ def self(self) -> Dict[str, Any]:
             href=urljoin(self.base_url, f"collections/{self.collection_id}"),
         )
 
-    def parent(self) -> Dict[str, Any]:
+    def parent(self) -> dict[str, Any]:
         """Create the `parent` link."""
         return dict(rel=Relations.parent, type=MimeTypes.json, href=self.base_url)
 
-    def items(self) -> Dict[str, Any]:
+    def items(self) -> dict[str, Any]:
         """Create the `items` link."""
         return dict(
             rel="items",
@@ -62,7 +62,7 @@ def items(self) -> Dict[str, Any]:
             href=urljoin(self.base_url, f"collections/{self.collection_id}/items"),
         )
 
-    def create_links(self) -> List[Dict[str, Any]]:
+    def create_links(self) -> list[dict[str, Any]]:
         """Return all inferred links."""
         return [self.self(), self.parent(), self.items(), self.root()]
 
@@ -73,7 +73,7 @@ class ItemLinks(BaseLinks):
 
     item_id: str = attr.ib()
 
-    def self(self) -> Dict[str, Any]:
+    def self(self) -> dict[str, Any]:
         """Create the `self` link."""
         return dict(
             rel=Relations.self,
@@ -84,7 +84,7 @@ def self(self) -> Dict[str, Any]:
             ),
         )
 
-    def parent(self) -> Dict[str, Any]:
+    def parent(self) -> dict[str, Any]:
         """Create the `parent` link."""
         return dict(
             rel=Relations.parent,
@@ -92,7 +92,7 @@ def parent(self) -> Dict[str, Any]:
             href=urljoin(self.base_url, f"collections/{self.collection_id}"),
         )
 
-    def collection(self) -> Dict[str, Any]:
+    def collection(self) -> dict[str, Any]:
         """Create the `collection` link."""
         return dict(
             rel=Relations.collection,
@@ -100,7 +100,7 @@ def collection(self) -> Dict[str, Any]:
             href=urljoin(self.base_url, f"collections/{self.collection_id}"),
         )
 
-    def create_links(self) -> List[Dict[str, Any]]:
+    def create_links(self) -> list[dict[str, Any]]:
         """Return all inferred links."""
         links = [
             self.self(),
diff --git a/stac_fastapi/types/stac_fastapi/types/rfc3339.py b/stac_fastapi/types/stac_fastapi/types/rfc3339.py
index 3c4cee30d..6e953ebd4 100644
--- a/stac_fastapi/types/stac_fastapi/types/rfc3339.py
+++ b/stac_fastapi/types/stac_fastapi/types/rfc3339.py
@@ -1,4 +1,5 @@
 """rfc3339."""
+
 import re
 from datetime import datetime, timezone
 from typing import Optional, Tuple
diff --git a/stac_fastapi/types/stac_fastapi/types/search.py b/stac_fastapi/types/stac_fastapi/types/search.py
index 8d086a9be..f049ccd86 100644
--- a/stac_fastapi/types/stac_fastapi/types/search.py
+++ b/stac_fastapi/types/stac_fastapi/types/search.py
@@ -5,10 +5,9 @@
 
 import abc
 import operator
-from datetime import datetime
 from enum import auto
 from types import DynamicClassAttribute
-from typing import Any, Callable, Dict, Generator, List, Optional, Union
+from typing import Any, Callable, Optional, Union
 
 import attr
 from geojson_pydantic.geometries import (
@@ -20,38 +19,26 @@
     Polygon,
     _GeometryBase,
 )
-from pydantic import BaseModel, ConstrainedInt, validator
-from pydantic.errors import NumberNotGtError
-from pydantic.validators import int_validator
+from pydantic import BaseModel, PositiveInt, field_validator, model_validator
+from pydantic.functional_validators import AfterValidator
 from stac_pydantic.shared import BBox
 from stac_pydantic.utils import AutoValueEnum
+from typing_extensions import Annotated, Self
 
 from stac_fastapi.types.rfc3339 import rfc3339_str_to_datetime, str_to_interval
 
-# Be careful: https://github.com/samuelcolvin/pydantic/issues/1423#issuecomment-642797287
-NumType = Union[float, int]
-
 
-class Limit(ConstrainedInt):
-    """An positive integer that maxes out at 10,000."""
-
-    ge: int = 1
-    le: int = 10_000
+def check_limit(v: int) -> int:
+    """Validate input value."""
+    if v > 10000:
+        return 10000
+    else:
+        return v
 
-    @classmethod
-    def __get_validators__(cls) -> Generator[Callable[..., Any], None, None]:
-        """Yield the relevant validators."""
-        yield int_validator
-        yield cls.validate
 
-    @classmethod
-    def validate(cls, value: int) -> int:
-        """Validate the integer value."""
-        if value < cls.ge:
-            raise NumberNotGtError(limit_value=cls.ge)
-        if value > cls.le:
-            return cls.le
-        return value
+Limit = Annotated[PositiveInt, AfterValidator(check_limit)]
+# Be careful: https://github.com/samuelcolvin/pydantic/issues/1423#issuecomment-642797287
+NumType = Union[float, int]
 
 
 class Operator(str, AutoValueEnum):
@@ -76,7 +63,7 @@ def operator(self) -> Callable[[Any, Any], bool]:
         return getattr(operator, self._value_)
 
 
-def str2list(x: str) -> Optional[List]:
+def str2list(x: str) -> Optional[list]:
     """Convert string to list base on , delimiter."""
     if x:
         return x.split(",")
@@ -86,7 +73,7 @@ def str2list(x: str) -> Optional[List]:
 class APIRequest(abc.ABC):
     """Generic API Request base class."""
 
-    def kwargs(self) -> Dict:
+    def kwargs(self) -> dict:
         """Transform api request params into format which matches the signature of the
         endpoint."""
         return self.__dict__
@@ -115,13 +102,13 @@ class BaseSearchPostRequest(BaseModel):
     https://github.com/stac-utils/stac-pydantic/pull/100
     """
 
-    collections: Optional[List[str]]
-    ids: Optional[List[str]]
-    bbox: Optional[BBox]
+    collections: Optional[list[str]] = None
+    ids: Optional[list[str]] = None
+    bbox: Optional[BBox] = None
     intersects: Optional[
         Union[Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon]
-    ]
-    datetime: Optional[str]
+    ] = None
+    datetime: Optional[str] = None
     limit: Optional[Limit] = 10
 
     @property
@@ -136,14 +123,15 @@ def end_date(self) -> Optional[datetime]:
         interval = str_to_interval(self.datetime)
         return interval[1] if interval else None
 
-    @validator("intersects")
-    def validate_spatial(cls, v, values):
+    @model_validator(mode="before")
+    def validate_spatial(self) -> Self:
         """Check bbox and intersects are not both supplied."""
-        if v and values["bbox"]:
+        if self.get("intersects") and self.get("bbox") is not None:
             raise ValueError("intersects and bbox parameters are mutually exclusive")
-        return v
+        return self
 
-    @validator("bbox")
+    @field_validator("bbox")
+    @classmethod
     def validate_bbox(cls, v: BBox):
         """Check order of supplied bbox coordinates."""
         if v:
@@ -173,7 +161,8 @@ def validate_bbox(cls, v: BBox):
 
         return v
 
-    @validator("datetime")
+    @field_validator("datetime")
+    @classmethod
     def validate_datetime(cls, v):
         """Validate datetime."""
         if "/" in v:
diff --git a/stac_fastapi/types/stac_fastapi/types/stac.py b/stac_fastapi/types/stac_fastapi/types/stac.py
deleted file mode 100644
index f0876cef0..000000000
--- a/stac_fastapi/types/stac_fastapi/types/stac.py
+++ /dev/null
@@ -1,90 +0,0 @@
-"""STAC types."""
-import sys
-from typing import Any, Dict, List, Literal, Optional, Union
-
-# Avoids a Pydantic error:
-# TypeError: You should use `typing_extensions.TypedDict` instead of
-# `typing.TypedDict` with Python < 3.9.2.  Without it, there is no way to
-# differentiate required and optional fields when subclassed.
-if sys.version_info < (3, 9, 2):
-    from typing_extensions import TypedDict
-else:
-    from typing import TypedDict
-
-NumType = Union[float, int]
-
-
-class LandingPage(TypedDict, total=False):
-    """STAC Landing Page."""
-
-    type: str
-    stac_version: str
-    stac_extensions: Optional[List[str]]
-    id: str
-    title: str
-    description: str
-    conformsTo: List[str]
-    links: List[Dict[str, Any]]
-
-
-class Conformance(TypedDict):
-    """STAC Conformance Classes."""
-
-    conformsTo: List[str]
-
-
-class Catalog(TypedDict, total=False):
-    """STAC Catalog."""
-
-    type: str
-    stac_version: str
-    stac_extensions: Optional[List[str]]
-    id: str
-    title: Optional[str]
-    description: str
-    links: List[Dict[str, Any]]
-
-
-class Collection(Catalog, total=False):
-    """STAC Collection."""
-
-    keywords: List[str]
-    license: str
-    providers: List[Dict[str, Any]]
-    extent: Dict[str, Any]
-    summaries: Dict[str, Any]
-    assets: Dict[str, Any]
-
-
-class Item(TypedDict, total=False):
-    """STAC Item."""
-
-    type: Literal["Feature"]
-    stac_version: str
-    stac_extensions: Optional[List[str]]
-    id: str
-    geometry: Dict[str, Any]
-    bbox: List[NumType]
-    properties: Dict[str, Any]
-    links: List[Dict[str, Any]]
-    assets: Dict[str, Any]
-    collection: str
-
-
-class ItemCollection(TypedDict, total=False):
-    """STAC Item Collection."""
-
-    type: Literal["FeatureCollection"]
-    features: List[Item]
-    links: List[Dict[str, Any]]
-    context: Optional[Dict[str, int]]
-
-
-class Collections(TypedDict, total=False):
-    """All collections endpoint.
-
-    https://github.com/radiantearth/stac-api-spec/tree/master/collections
-    """
-
-    collections: List[Collection]
-    links: List[Dict[str, Any]]
diff --git a/stac_fastapi/types/stac_fastapi/types/version.py b/stac_fastapi/types/stac_fastapi/types/version.py
index bb0c7c379..54c068f57 100644
--- a/stac_fastapi/types/stac_fastapi/types/version.py
+++ b/stac_fastapi/types/stac_fastapi/types/version.py
@@ -1,2 +1,3 @@
 """Library version."""
+
 __version__ = "2.4.9"