diff --git a/src/pdm/backend/_vendor/packaging/specifiers.py b/src/pdm/backend/_vendor/packaging/specifiers.py
index 2b9feb0..645214a 100644
--- a/src/pdm/backend/_vendor/packaging/specifiers.py
+++ b/src/pdm/backend/_vendor/packaging/specifiers.py
@@ -4,8 +4,8 @@
 """
 .. testsetup::
 
-    from pdm.backend._vendor.packaging.specifiers import Specifier, SpecifierSet, InvalidSpecifier
-    from pdm.backend._vendor.packaging.version import Version
+    from packaging.specifiers import Specifier, SpecifierSet, InvalidSpecifier
+    from packaging.version import Version
 """
 
 import abc
diff --git a/src/pdm/backend/_vendor/packaging/version.py b/src/pdm/backend/_vendor/packaging/version.py
index b9b6184..e5c738c 100644
--- a/src/pdm/backend/_vendor/packaging/version.py
+++ b/src/pdm/backend/_vendor/packaging/version.py
@@ -4,7 +4,7 @@
 """
 .. testsetup::
 
-    from pdm.backend._vendor.packaging.version import parse, Version
+    from packaging.version import parse, Version
 """
 
 import collections
diff --git a/src/pdm/backend/_vendor/pyproject_metadata/__init__.py b/src/pdm/backend/_vendor/pyproject_metadata/__init__.py
index 8897c69..a291510 100644
--- a/src/pdm/backend/_vendor/pyproject_metadata/__init__.py
+++ b/src/pdm/backend/_vendor/pyproject_metadata/__init__.py
@@ -13,10 +13,10 @@ import typing
 from collections.abc import Mapping
 from typing import Any
 
-import pdm.backend._vendor.packaging.markers as pkg_markers
-import pdm.backend._vendor.packaging.requirements as pkg_requirements
-import pdm.backend._vendor.packaging.specifiers as pkg_specifiers
-import pdm.backend._vendor.packaging.version as pkg_version
+import packaging.markers as pkg_markers
+import packaging.requirements as pkg_requirements
+import packaging.specifiers as pkg_specifiers
+import packaging.version as pkg_version
 
 
 __version__ = '0.7.0'
diff --git a/src/pdm/backend/_vendor/tomli_w/__init__.py b/src/pdm/backend/_vendor/tomli_w/__init__.py
index 5324bfa..d7db4cd 100644
--- a/src/pdm/backend/_vendor/tomli_w/__init__.py
+++ b/src/pdm/backend/_vendor/tomli_w/__init__.py
@@ -1,4 +1,4 @@
 __all__ = ("dumps", "dump")
 __version__ = "1.0.0"  # DO NOT EDIT THIS LINE MANUALLY. LET bump2version UTILITY DO IT
 
-from pdm.backend._vendor.tomli_w._writer import dump, dumps
+from tomli_w._writer import dump, dumps
diff --git a/src/pdm/backend/_vendor/validate_pyproject/api.py b/src/pdm/backend/_vendor/validate_pyproject/api.py
index c2fee43..0dc85a0 100644
--- a/src/pdm/backend/_vendor/validate_pyproject/api.py
+++ b/src/pdm/backend/_vendor/validate_pyproject/api.py
@@ -23,7 +23,7 @@ from typing import (
 )
 
 from . import errors, formats
-from ._vendor import fastjsonschema as FJS
+import fastjsonschema as FJS
 from .error_reporting import detailed_errors
 from .extra_validations import EXTRA_VALIDATIONS
 from .types import FormatValidationFn, Schema, ValidationFn
diff --git a/src/pdm/backend/_vendor/validate_pyproject/cli.py b/src/pdm/backend/_vendor/validate_pyproject/cli.py
index cdccf40..1232c7d 100644
--- a/src/pdm/backend/_vendor/validate_pyproject/cli.py
+++ b/src/pdm/backend/_vendor/validate_pyproject/cli.py
@@ -36,7 +36,7 @@ try:  # pragma: no cover
     if sys.version_info[:2] >= (3, 11):
         from tomllib import TOMLDecodeError, loads
     else:
-        from pdm.backend._vendor.tomli import TOMLDecodeError, loads
+        from tomli import TOMLDecodeError, loads
 except ImportError:  # pragma: no cover
     try:
         from toml import TomlDecodeError as TOMLDecodeError  # type: ignore
diff --git a/src/pdm/backend/_vendor/validate_pyproject/error_reporting.py b/src/pdm/backend/_vendor/validate_pyproject/error_reporting.py
index 3a9c6af..bdb82cc 100644
--- a/src/pdm/backend/_vendor/validate_pyproject/error_reporting.py
+++ b/src/pdm/backend/_vendor/validate_pyproject/error_reporting.py
@@ -7,7 +7,7 @@ from contextlib import contextmanager
 from textwrap import indent, wrap
 from typing import Any, Dict, Iterator, List, Optional, Sequence, Union, cast
 
-from ._vendor.fastjsonschema import JsonSchemaValueException
+from fastjsonschema import JsonSchemaValueException
 
 _logger = logging.getLogger(__name__)
 
diff --git a/src/pdm/backend/_vendor/validate_pyproject/errors.py b/src/pdm/backend/_vendor/validate_pyproject/errors.py
index 289e38f..e864134 100644
--- a/src/pdm/backend/_vendor/validate_pyproject/errors.py
+++ b/src/pdm/backend/_vendor/validate_pyproject/errors.py
@@ -1,6 +1,6 @@
 from textwrap import dedent
 
-from ._vendor.fastjsonschema import (
+from fastjsonschema import (
     JsonSchemaDefinitionException,
     JsonSchemaException,
     JsonSchemaValueException,
diff --git a/src/pdm/backend/_vendor/validate_pyproject/formats.py b/src/pdm/backend/_vendor/validate_pyproject/formats.py
index d55fb79..638ac11 100644
--- a/src/pdm/backend/_vendor/validate_pyproject/formats.py
+++ b/src/pdm/backend/_vendor/validate_pyproject/formats.py
@@ -61,7 +61,7 @@ def pep508_identifier(name: str) -> bool:
 
 try:
     try:
-        from pdm.backend._vendor.packaging import requirements as _req
+        from packaging import requirements as _req
     except ImportError:  # pragma: no cover
         # let's try setuptools vendored version
         from setuptools._vendor.packaging import requirements as _req  # type: ignore
diff --git a/src/pdm/backend/_vendor/validate_pyproject/pre_compile/__init__.py b/src/pdm/backend/_vendor/validate_pyproject/pre_compile/__init__.py
index 0722ca3..e9ea1ae 100644
--- a/src/pdm/backend/_vendor/validate_pyproject/pre_compile/__init__.py
+++ b/src/pdm/backend/_vendor/validate_pyproject/pre_compile/__init__.py
@@ -6,7 +6,7 @@ from types import MappingProxyType
 from typing import TYPE_CHECKING, Dict, Mapping, Optional, Sequence, Union
 
 from .. import api, dist_name, types
-from .._vendor import fastjsonschema as FJS
+import fastjsonschema as FJS
 
 if sys.version_info[:2] >= (3, 8):  # pragma: no cover
     from importlib import metadata as _M
diff --git a/src/pdm/backend/config.py b/src/pdm/backend/config.py
index 7074cb2..b6e2124 100644
--- a/src/pdm/backend/config.py
+++ b/src/pdm/backend/config.py
@@ -6,9 +6,9 @@ import sys
 from pathlib import Path
 from typing import Any, TypeVar
 
-from pdm.backend._vendor import tomli_w
-from pdm.backend._vendor.pyproject_metadata import StandardMetadata
-from pdm.backend._vendor.validate_pyproject import api, errors
+import tomli_w
+from pyproject_metadata import StandardMetadata
+from validate_pyproject import api, errors
 from pdm.backend.exceptions import ConfigError, ValidationError
 from pdm.backend.structures import Table
 from pdm.backend.utils import find_packages_iter
@@ -16,7 +16,7 @@ from pdm.backend.utils import find_packages_iter
 if sys.version_info >= (3, 11):
     import tomllib
 else:
-    import pdm.backend._vendor.tomli as tomllib
+    import tomli as tomllib
 
 T = TypeVar("T")
 
diff --git a/src/pdm/backend/hooks/version/scm.py b/src/pdm/backend/hooks/version/scm.py
index 14a39a9..8c97e70 100644
--- a/src/pdm/backend/hooks/version/scm.py
+++ b/src/pdm/backend/hooks/version/scm.py
@@ -15,7 +15,7 @@ from datetime import datetime
 from pathlib import Path
 from typing import Any, Iterable, NamedTuple
 
-from pdm.backend._vendor.packaging.version import Version
+from packaging.version import Version
 
 DEFAULT_TAG_REGEX = re.compile(
     r"^(?:[\w-]+-)?(?P<version>[vV]?\d+(?:\.\d+){0,2}[^\+]*)(?:\+.*)?$"
diff --git a/src/pdm/backend/intree.py b/src/pdm/backend/intree.py
index 4a77e83..b19a9d7 100644
--- a/src/pdm/backend/intree.py
+++ b/src/pdm/backend/intree.py
@@ -8,7 +8,7 @@ import pdm.backend as api
 if sys.version_info >= (3, 11):
     import tomllib
 else:
-    import pdm.backend._vendor.tomli as tomllib
+    import tomli as tomllib
 
 
 def get_requires_for_build_wheel(
diff --git a/src/pdm/backend/utils.py b/src/pdm/backend/utils.py
index 390c6fc..18a6ff1 100644
--- a/src/pdm/backend/utils.py
+++ b/src/pdm/backend/utils.py
@@ -13,10 +13,10 @@ from fnmatch import fnmatchcase
 from pathlib import Path
 from typing import Callable, Generator, Iterable, Match
 
-from pdm.backend._vendor.packaging import tags
-from pdm.backend._vendor.packaging.markers import Marker
-from pdm.backend._vendor.packaging.requirements import Requirement
-from pdm.backend._vendor.packaging.version import InvalidVersion, Version
+from packaging import tags
+from packaging.markers import Marker
+from packaging.requirements import Requirement
+from packaging.version import InvalidVersion, Version
 from pdm.backend.macosx_platform import calculate_macosx_platform_tag
 
 
diff --git a/src/pdm/backend/wheel.py b/src/pdm/backend/wheel.py
index e33cbdb..5d87939 100644
--- a/src/pdm/backend/wheel.py
+++ b/src/pdm/backend/wheel.py
@@ -15,8 +15,8 @@ from base64 import urlsafe_b64encode
 from pathlib import Path
 from typing import IO, Any, Iterable, Mapping, NamedTuple, cast
 
-from pdm.backend._vendor.packaging import tags
-from pdm.backend._vendor.packaging.specifiers import SpecifierSet
+from packaging import tags
+from packaging.specifiers import SpecifierSet
 from pdm.backend._vendor.packaging.utils import canonicalize_name
 from pdm.backend.base import Builder
 from pdm.backend.hooks import Context