diff --git a/craft_parts/plugins/__init__.py b/craft_parts/plugins/__init__.py
index 6e62e2fb..356fccac 100644
--- a/craft_parts/plugins/__init__.py
+++ b/craft_parts/plugins/__init__.py
@@ -18,7 +18,6 @@
 
 from .base import Plugin, extract_plugin_properties
 from .plugins import (
-    PluginProperties,
     extract_part_properties,
     get_plugin,
     get_plugin_class,
@@ -27,6 +26,7 @@
     unregister,
     unregister_all,
 )
+from .properties import PluginProperties
 from .validator import PluginEnvironmentValidator
 
 __all__ = [
diff --git a/craft_parts/plugins/ant_plugin.py b/craft_parts/plugins/ant_plugin.py
index daa204a7..4310c2ca 100644
--- a/craft_parts/plugins/ant_plugin.py
+++ b/craft_parts/plugins/ant_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2022 Canonical Ltd.
+# Copyright 2022,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -20,7 +20,7 @@
 import os
 import shlex
 from collections.abc import Iterator
-from typing import Any, cast
+from typing import Any, Literal, cast
 from urllib.parse import urlsplit
 
 from overrides import override
@@ -34,8 +34,9 @@
 logger = logging.getLogger(__name__)
 
 
-class AntPluginProperties(PluginProperties):
+class AntPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the Ant plugin."""
+    plugin: Literal["ant"] = "ant"
 
     ant_build_targets: list[str] = []
     ant_build_file: str | None = None
@@ -43,22 +44,6 @@ class AntPluginProperties(PluginProperties):
 
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "AntPluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="ant", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class AntPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the Ant plugin.
diff --git a/craft_parts/plugins/autotools_plugin.py b/craft_parts/plugins/autotools_plugin.py
index 3e8bfa23..aced7205 100644
--- a/craft_parts/plugins/autotools_plugin.py
+++ b/craft_parts/plugins/autotools_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020 Canonical Ltd.
+# Copyright 2020,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -16,7 +16,7 @@
 
 """The autotools plugin implementation."""
 
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -24,8 +24,9 @@
 from .properties import PluginProperties
 
 
-class AutotoolsPluginProperties(PluginProperties):
+class AutotoolsPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the autotools plugin."""
+    plugin: Literal["autotools"] = "autotools"
 
     autotools_configure_parameters: list[str] = []
     autotools_bootstrap_parameters: list[str] = []
@@ -33,22 +34,6 @@ class AutotoolsPluginProperties(PluginProperties):
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "AutotoolsPluginProperties":
-        """Populate autotools properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="autotools", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class AutotoolsPlugin(Plugin):
     """The autotools plugin is used for autotools-based parts.
diff --git a/craft_parts/plugins/base.py b/craft_parts/plugins/base.py
index c44dab37..37ce5d1d 100644
--- a/craft_parts/plugins/base.py
+++ b/craft_parts/plugins/base.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020-2023 Canonical Ltd.
+# Copyright 2020-2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -16,9 +16,14 @@
 
 """Plugin base class and definitions."""
 
+from __future__ import annotations
+
 import abc
 from copy import deepcopy
-from typing import TYPE_CHECKING, Any
+from typing import TYPE_CHECKING, Any, ClassVar, Collection
+from typing_extensions import Self
+
+import pydantic
 
 from craft_parts.actions import ActionProperties
 
@@ -123,7 +128,7 @@ def _get_java_post_build_commands(self) -> list[str]:
 
 
 def extract_plugin_properties(
-    data: dict[str, Any], *, plugin_name: str, required: list[str] | None = None
+    data: dict[str, Any], *, plugin_name: str, required: Collection[str] | None = None
 ) -> dict[str, Any]:
     """Obtain plugin-specific entries from part properties.
 
diff --git a/craft_parts/plugins/cmake_plugin.py b/craft_parts/plugins/cmake_plugin.py
index f8398fb5..3f317548 100644
--- a/craft_parts/plugins/cmake_plugin.py
+++ b/craft_parts/plugins/cmake_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020-2022 Canonical Ltd.
+# Copyright 2020-2022,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -16,7 +16,7 @@
 
 """The cmake plugin."""
 
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -24,8 +24,9 @@
 from .properties import PluginProperties
 
 
-class CMakePluginProperties(PluginProperties):
+class CMakePluginProperties(PluginProperties, frozen=True):
     """The part properties used by the cmake plugin."""
+    plugin: Literal["cmake"] = "cmake"
 
     cmake_parameters: list[str] = []
     cmake_generator: str = "Unix Makefiles"
@@ -33,22 +34,6 @@ class CMakePluginProperties(PluginProperties):
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "CMakePluginProperties":
-        """Populate class attributes from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="cmake", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class CMakePlugin(Plugin):
     """The cmake plugin is useful for building cmake based parts.
diff --git a/craft_parts/plugins/dotnet_plugin.py b/craft_parts/plugins/dotnet_plugin.py
index feae2275..932e55a8 100644
--- a/craft_parts/plugins/dotnet_plugin.py
+++ b/craft_parts/plugins/dotnet_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2021 Canonical Ltd.
+# Copyright 2021,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -17,7 +17,7 @@
 """The Dotnet plugin."""
 
 import logging
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -28,8 +28,9 @@
 logger = logging.getLogger(__name__)
 
 
-class DotnetPluginProperties(PluginProperties):
+class DotnetPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the Dotnet plugin."""
+    plugin: Literal["dotnet"] = "dotnet"
 
     dotnet_build_configuration: str = "Release"
     dotnet_self_contained_runtime_identifier: str | None = None
@@ -37,22 +38,6 @@ class DotnetPluginProperties(PluginProperties):
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "DotnetPluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="dotnet", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class DotPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the Dotnet plugin.
diff --git a/craft_parts/plugins/dump_plugin.py b/craft_parts/plugins/dump_plugin.py
index 54a00cdc..6a0f2016 100644
--- a/craft_parts/plugins/dump_plugin.py
+++ b/craft_parts/plugins/dump_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020 Canonical Ltd.
+# Copyright 2020,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -19,7 +19,7 @@
 This plugin just dumps the content from a specified part source.
 """
 
-from typing import Any
+from typing import Any, Literal
 
 from overrides import override
 
@@ -27,25 +27,10 @@
 from .properties import PluginProperties
 
 
-class DumpPluginProperties(PluginProperties):
+class DumpPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the dump plugin."""
-
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "DumpPluginProperties":
-        """Populate dump properties from the part specification.
-
-        'source' is a required part property.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise ValueError: If a required property is not found.
-        """
-        if "source" not in data:
-            raise ValueError("'source' is required by the dump plugin")
-        return cls()
+    plugin: Literal["dump"] = "dump"
+    source: str
 
 
 class DumpPlugin(Plugin):
diff --git a/craft_parts/plugins/go_plugin.py b/craft_parts/plugins/go_plugin.py
index 4a2a1605..5eb7348d 100644
--- a/craft_parts/plugins/go_plugin.py
+++ b/craft_parts/plugins/go_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020-2021 Canonical Ltd.
+# Copyright 2020-2021,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -17,7 +17,7 @@
 """The Go plugin."""
 
 import logging
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -30,8 +30,9 @@
 logger = logging.getLogger(__name__)
 
 
-class GoPluginProperties(PluginProperties):
+class GoPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the Go plugin."""
+    plugin: Literal["go"] = "go"
 
     go_buildtags: list[str] = []
     go_generate: list[str] = []
@@ -39,22 +40,6 @@ class GoPluginProperties(PluginProperties):
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "GoPluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="go", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class GoPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the Go plugin.
diff --git a/craft_parts/plugins/make_plugin.py b/craft_parts/plugins/make_plugin.py
index 7ce44110..574bffcc 100644
--- a/craft_parts/plugins/make_plugin.py
+++ b/craft_parts/plugins/make_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020-2021 Canonical Ltd.
+# Copyright 2020-2021,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -16,7 +16,7 @@
 
 """The make plugin implementation."""
 
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -24,30 +24,15 @@
 from .properties import PluginProperties
 
 
-class MakePluginProperties(PluginProperties):
+class MakePluginProperties(PluginProperties, frozen=True):
     """The part properties used by the make plugin."""
+    plugin: Literal["make"] = "make"
 
     make_parameters: list[str] = []
 
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "MakePluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="make", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class MakePlugin(Plugin):
     """A plugin useful for building make-based parts.
diff --git a/craft_parts/plugins/maven_plugin.py b/craft_parts/plugins/maven_plugin.py
index df7dd8d7..c1ffadef 100644
--- a/craft_parts/plugins/maven_plugin.py
+++ b/craft_parts/plugins/maven_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2015-2023 Canonical Ltd.
+# Copyright 2015-2023,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -19,7 +19,7 @@
 import os
 import re
 from pathlib import Path
-from typing import Any, cast
+from typing import Any, Literal, cast
 from urllib.parse import urlparse
 from xml.etree import ElementTree
 
@@ -32,30 +32,15 @@
 from .properties import PluginProperties
 
 
-class MavenPluginProperties(PluginProperties):
+class MavenPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the maven plugin."""
+    plugin: Literal["maven"] = "maven"
 
     maven_parameters: list[str] = []
 
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "MavenPluginProperties":
-        """Populate class attributes from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="maven", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class MavenPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the maven plugin.
diff --git a/craft_parts/plugins/meson_plugin.py b/craft_parts/plugins/meson_plugin.py
index ebd7229d..0e8d1350 100644
--- a/craft_parts/plugins/meson_plugin.py
+++ b/craft_parts/plugins/meson_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2022 Canonical Ltd.
+# Copyright 2022,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -19,7 +19,7 @@
 
 import logging
 import shlex
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -30,30 +30,15 @@
 logger = logging.getLogger(__name__)
 
 
-class MesonPluginProperties(PluginProperties):
+class MesonPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the Meson plugin."""
+    plugin: Literal["meson"] = "meson"
 
     meson_parameters: list[str] = []
 
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "MesonPluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="meson", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class MesonPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the Meson plugin.
diff --git a/craft_parts/plugins/nil_plugin.py b/craft_parts/plugins/nil_plugin.py
index a5957e2d..f09c4f1e 100644
--- a/craft_parts/plugins/nil_plugin.py
+++ b/craft_parts/plugins/nil_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020 Canonical Ltd.
+# Copyright 2020,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -20,7 +20,7 @@
 automatically included, e.g. stage-packages.
 """
 
-from typing import Any
+from typing import Any, ClassVar, Collection, Literal
 
 from overrides import override
 
@@ -28,19 +28,11 @@
 from .properties import PluginProperties
 
 
-class NilPluginProperties(PluginProperties):
+class NilPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the nil plugin."""
+    plugin: Literal["nil"] = "nil"
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "NilPluginProperties":  # noqa: ARG003
-        """Populate class attributes from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-        """
-        return cls()
+    _required_fields: ClassVar[Collection[str]] = ()
 
 
 class NilPlugin(Plugin):
diff --git a/craft_parts/plugins/npm_plugin.py b/craft_parts/plugins/npm_plugin.py
index 252e942e..3ffa4373 100644
--- a/craft_parts/plugins/npm_plugin.py
+++ b/craft_parts/plugins/npm_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2022 Canonical Ltd.
+# Copyright 2022,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -21,7 +21,7 @@
 import platform
 import re
 from textwrap import dedent
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 import requests
 from overrides import override
@@ -47,8 +47,9 @@
 _NODE_ARCH_FROM_PLATFORM = {"x86_64": {"32bit": "x86", "64bit": "x64"}}
 
 
-class NpmPluginProperties(PluginProperties):
+class NpmPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the npm plugin."""
+    plugin: Literal["npm"] = "npm"
 
     # part properties required by the plugin
     npm_include_node: bool = False
@@ -66,22 +67,6 @@ def node_version_defined(self) -> Self:
             )
         return self
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "NpmPluginProperties":
-        """Populate class attributes from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="npm", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class NpmPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the npm plugin.
diff --git a/craft_parts/plugins/properties.py b/craft_parts/plugins/properties.py
index 7ccace90..eb927d5f 100644
--- a/craft_parts/plugins/properties.py
+++ b/craft_parts/plugins/properties.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2021-2023 Canonical Ltd.
+# Copyright 2021-2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -16,23 +16,16 @@
 
 """Definitions and helpers for plugin options."""
 
-from typing import Any
+from typing import Any, ClassVar, Collection
+from typing_extensions import Self
 
-from pydantic import BaseModel, ConfigDict
+import pydantic
 
+from . import base
 
-class PluginPropertiesModel(BaseModel):
-    """Model for plugins properties using pydantic validation."""
 
-    model_config = ConfigDict(
-        validate_assignment=True,
-        extra="forbid",
-        frozen=True,
-        alias_generator=lambda s: s.replace("_", "-"),
-    )
-
-
-class PluginProperties(PluginPropertiesModel):
+# `frozen=True` here so that pyright will warn if child classes are mutable.
+class PluginProperties(pydantic.BaseModel, frozen=True):
     """Options specific to a plugin.
 
     PluginProperties should be subclassed into plugin-specific property
@@ -42,19 +35,34 @@ class PluginProperties(PluginPropertiesModel):
     build step is dirty. This can be overridden in each plugin if needed.
     """
 
+    model_config = pydantic.ConfigDict(
+        validate_assignment=True,
+        extra="forbid",
+        frozen=True,
+        alias_generator=lambda s: s.replace("_", "-"),
+    )
+    plugin: str = ""
+
+    _required_fields: ClassVar[Collection[str]] = ("source",)
+
     @classmethod
-    def unmarshal(cls, data: dict[str, Any]) -> "PluginProperties":  # noqa: ARG003
+    def unmarshal(cls, data: dict[str, Any]) -> Self:
         """Populate class attributes from the part specification.
 
         :param data: A dictionary containing part properties.
 
         :return: The populated plugin properties data object.
         """
-        return cls()
+        return cls.model_validate(
+            base.extract_plugin_properties(
+                data, plugin_name=cls.__fields__["plugin"].default,
+                required=cls._required_fields,
+            )
+        )
 
     def marshal(self) -> dict[str, Any]:
         """Obtain a dictionary containing the plugin properties."""
-        return self.dict(by_alias=True)
+        return self.model_dump(mode="json", by_alias=True, exclude={"plugin"})
 
     @classmethod
     def get_pull_properties(cls) -> list[str]:
@@ -65,4 +73,7 @@ def get_pull_properties(cls) -> list[str]:
     def get_build_properties(cls) -> list[str]:
         """Obtain the list of properties affecting the build stage."""
         properties = cls.schema(by_alias=True).get("properties")
-        return list(properties.keys()) if properties else []
+        if properties:
+            del properties["plugin"]
+            return list(properties)
+        return []
diff --git a/craft_parts/plugins/python_plugin.py b/craft_parts/plugins/python_plugin.py
index bb132d4a..34323be1 100644
--- a/craft_parts/plugins/python_plugin.py
+++ b/craft_parts/plugins/python_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2020-2023 Canonical Ltd.
+# Copyright 2020-2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -18,7 +18,7 @@
 
 import shlex
 from textwrap import dedent
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -26,8 +26,9 @@
 from .properties import PluginProperties
 
 
-class PythonPluginProperties(PluginProperties):
+class PythonPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the python plugin."""
+    plugin: Literal["python"] = "python"
 
     python_requirements: list[str] = []
     python_constraints: list[str] = []
@@ -36,22 +37,6 @@ class PythonPluginProperties(PluginProperties):
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "PythonPluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="python", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class PythonPlugin(Plugin):
     """A plugin to build python parts."""
diff --git a/craft_parts/plugins/qmake_plugin.py b/craft_parts/plugins/qmake_plugin.py
index d010bd0a..9391d276 100644
--- a/craft_parts/plugins/qmake_plugin.py
+++ b/craft_parts/plugins/qmake_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2023 Canonical Ltd.
+# Copyright 2023,2024 Canonical Ltd.
 # Copyright 2023 Scarlett Moore <sgmoore@kde.org>.
 #
 # This program is free software; you can redistribute it and/or
@@ -18,7 +18,7 @@
 
 """The qmake plugin."""
 
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 from typing_extensions import Self
@@ -27,8 +27,9 @@
 from .properties import PluginProperties
 
 
-class QmakePluginProperties(PluginProperties):
+class QmakePluginProperties(PluginProperties, frozen=True):
     """The part properties used by the qmake plugin."""
+    plugin: Literal["qmake"] = "qmake"
 
     qmake_parameters: list[str] = []
     qmake_project_file: str = ""
@@ -37,21 +38,6 @@ class QmakePluginProperties(PluginProperties):
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    def unmarshal(cls, data: dict[str, Any]) -> Self:
-        """Populate class attributes from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="qmake", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class QmakePlugin(Plugin):
     """The qmake plugin is useful for building qmake-based parts.
diff --git a/craft_parts/plugins/rust_plugin.py b/craft_parts/plugins/rust_plugin.py
index a8777f8e..084f796f 100644
--- a/craft_parts/plugins/rust_plugin.py
+++ b/craft_parts/plugins/rust_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2022-2023 Canonical Ltd.
+# Copyright 2022-2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -22,7 +22,7 @@
 import re
 import subprocess
 from textwrap import dedent
-from typing import Annotated, Any, cast
+from typing import Annotated, Any, Literal, cast
 
 from overrides import override
 from pydantic import AfterValidator
@@ -46,8 +46,9 @@ def _validate_list_is_unique(value: list) -> list:
 UniqueStrList = Annotated[list[str], AfterValidator(_validate_list_is_unique)]
 
 
-class RustPluginProperties(PluginProperties):
+class RustPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the Rust plugin."""
+    plugin: Literal["rust"] = "rust"
 
     # part properties required by the plugin
     rust_features: UniqueStrList = []
@@ -78,24 +79,6 @@ def validate_rust_channel(cls, value: str | None) -> str | None:
             return value
         raise ValueError(f"Invalid rust-channel: {value}")
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "RustPluginProperties":
-        """Populate class attributes from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data,
-            plugin_name="rust",
-            required=["source"],
-        )
-        return cls(**plugin_data)
-
 
 class RustPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the Rust plugin.
diff --git a/craft_parts/plugins/scons_plugin.py b/craft_parts/plugins/scons_plugin.py
index 53fd0eb8..373e7cf9 100644
--- a/craft_parts/plugins/scons_plugin.py
+++ b/craft_parts/plugins/scons_plugin.py
@@ -1,6 +1,6 @@
 # -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
 #
-# Copyright 2022 Canonical Ltd.
+# Copyright 2022,2024 Canonical Ltd.
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -16,7 +16,7 @@
 
 """The SCons plugin."""
 
-from typing import Any, cast
+from typing import Any, Literal, cast
 
 from overrides import override
 
@@ -27,30 +27,15 @@
 from .properties import PluginProperties
 
 
-class SConsPluginProperties(PluginProperties):
+class SConsPluginProperties(PluginProperties, frozen=True):
     """The part properties used by the SCons plugin."""
+    plugin: Literal["scons"] = "scons"
 
     scons_parameters: list[str] = []
 
     # part properties required by the plugin
     source: str
 
-    @classmethod
-    @override
-    def unmarshal(cls, data: dict[str, Any]) -> "SConsPluginProperties":
-        """Populate make properties from the part specification.
-
-        :param data: A dictionary containing part properties.
-
-        :return: The populated plugin properties data object.
-
-        :raise pydantic.ValidationError: If validation fails.
-        """
-        plugin_data = extract_plugin_properties(
-            data, plugin_name="scons", required=["source"]
-        )
-        return cls(**plugin_data)
-
 
 class SConsPluginEnvironmentValidator(validator.PluginEnvironmentValidator):
     """Check the execution environment for the SCons plugin.
diff --git a/tests/unit/plugins/test_base.py b/tests/unit/plugins/test_base.py
index 534865d4..54d72dbf 100644
--- a/tests/unit/plugins/test_base.py
+++ b/tests/unit/plugins/test_base.py
@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from typing import Any, cast
+from typing import Any, ClassVar, Collection, Literal, cast
 
 import pytest
 from craft_parts.infos import PartInfo, ProjectInfo
@@ -23,14 +23,11 @@
 from craft_parts.plugins.base import extract_plugin_properties
 
 
-class FooPluginProperties(PluginProperties):
+class FooPluginProperties(PluginProperties, frozen=True):
     """Test plugin properties."""
+    plugin: Literal["foo"] = "foo"
 
-    name: str
-
-    @classmethod
-    def unmarshal(cls, data: dict[str, Any]):
-        return cls(name=data.get("foo-name", "nothing"))
+    foo_name: str
 
 
 class FooPlugin(Plugin):
@@ -49,7 +46,7 @@ def get_build_environment(self) -> dict[str, str]:
 
     def get_build_commands(self) -> list[str]:
         options = cast(FooPluginProperties, self._options)
-        return ["hello", options.name]
+        return ["hello", options.foo_name]
 
 
 def test_plugin(new_dir):
diff --git a/tests/unit/plugins/test_dump_plugin.py b/tests/unit/plugins/test_dump_plugin.py
index 80561490..114fa85d 100644
--- a/tests/unit/plugins/test_dump_plugin.py
+++ b/tests/unit/plugins/test_dump_plugin.py
@@ -40,9 +40,8 @@ def setup_method_fixture(self, new_dir):
         self._plugin = DumpPlugin(properties=properties, part_info=part_info)
 
     def test_unmarshal_error(self):
-        with pytest.raises(ValueError) as raised:  # noqa: PT011
+        with pytest.raises(ValueError, match=r"source\n\s+Field required") as raised:
             DumpPlugin.properties_class.unmarshal({})
-        assert str(raised.value) == "'source' is required by the dump plugin"
 
     def test_get_build_packages(self):
         assert self._plugin.get_build_packages() == set()
diff --git a/tests/unit/plugins/test_plugins.py b/tests/unit/plugins/test_plugins.py
index 06503331..36e5b270 100644
--- a/tests/unit/plugins/test_plugins.py
+++ b/tests/unit/plugins/test_plugins.py
@@ -54,6 +54,7 @@ class TestGetPlugin:
             ("make", MakePlugin, {"source": "."}),
             ("meson", MesonPlugin, {"source": "."}),
             ("nil", NilPlugin, {}),
+            ("nil", NilPlugin, {"source": "."}),
             ("npm", NpmPlugin, {"source": "."}),
             ("python", PythonPlugin, {"source": "."}),
             ("qmake", QmakePlugin, {"source": "."}),
diff --git a/tests/unit/plugins/test_properties.py b/tests/unit/plugins/test_properties.py
index ddf6dba7..40667530 100644
--- a/tests/unit/plugins/test_properties.py
+++ b/tests/unit/plugins/test_properties.py
@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from typing import Any
+from typing import Any, Literal
 
 from craft_parts.plugins import PluginProperties
 
@@ -24,13 +24,10 @@ def test_properties_unmarshal():
     assert isinstance(prop, PluginProperties)
 
 
-class FooProperties(PluginProperties):
+class FooProperties(PluginProperties, frozen=True):
+    plugin: Literal["foo"] = "foo"
     foo_parameters: list[str] | None = None
 
-    @classmethod
-    def unmarshal(cls, data: dict[str, Any]) -> "FooProperties":
-        return cls(**data)
-
 
 def test_properties_marshal():
     prop = FooProperties.unmarshal({"foo-parameters": ["foo", "bar"]})
diff --git a/tests/unit/plugins/test_validator.py b/tests/unit/plugins/test_validator.py
index 0494b1f7..8e62a285 100644
--- a/tests/unit/plugins/test_validator.py
+++ b/tests/unit/plugins/test_validator.py
@@ -53,7 +53,7 @@ def part_info(new_dir):
 
 
 @dataclass
-class FooPluginProperties(PluginProperties):
+class FooPluginProperties(PluginProperties, frozen=True):
     """Test plugin properties."""
 
     @classmethod