diff --git a/src/manifestoo_core/metadata.py b/src/manifestoo_core/metadata.py
index ebbea3b..bc6508d 100644
--- a/src/manifestoo_core/metadata.py
+++ b/src/manifestoo_core/metadata.py
@@ -5,7 +5,7 @@
 from dataclasses import dataclass
 from email.message import Message
 from pathlib import Path
-from typing import Dict, Iterator, List, Optional, Sequence, Set, Tuple, Union
+from typing import Dict, Iterator, List, Literal, Optional, Sequence, Set, Tuple, Union
 
 if sys.version_info >= (3, 8):
     from typing import TypedDict
@@ -37,11 +37,14 @@
     r"^odoo(\d{1,2})?[-_]addon[-_](?P<addon_name>[a-zA-Z0-9_-]+)$",
 )
 
+PostVersionStrategyOverrideStr = Literal[".N", "none", ".99.devN", "+1.devN"]
+
 __all__ = [
     "POST_VERSION_STRATEGY_DOT_N",
     "POST_VERSION_STRATEGY_NINETYNINE_DEVN",
     "POST_VERSION_STRATEGY_NONE",
     "POST_VERSION_STRATEGY_P1_DEVN",
+    "PostVersionStrategyOverrideStr",
     "metadata_from_addon_dir",
     "addon_name_to_distribution_name",
     "addon_name_to_requirement",
@@ -79,7 +82,7 @@ class MetadataOptions(TypedDict, total=False):
     external_dependencies_only: Optional[bool]
     odoo_series_override: Optional[str]
     odoo_version_override: Optional[str]
-    post_version_strategy_override: Optional[str]
+    post_version_strategy_override: Optional[PostVersionStrategyOverrideStr]
 
 
 def metadata_from_addon_dir(
diff --git a/tests/test_metadata.py b/tests/test_metadata.py
index bf7aa2e..7346c04 100644
--- a/tests/test_metadata.py
+++ b/tests/test_metadata.py
@@ -15,6 +15,7 @@
     POST_VERSION_STRATEGY_NINETYNINE_DEVN,
     POST_VERSION_STRATEGY_NONE,
     POST_VERSION_STRATEGY_P1_DEVN,
+    PostVersionStrategyOverrideStr,
     _author_email,
     _filter_odoo_addon_dependencies,
     _no_nl,
@@ -54,7 +55,7 @@ def _m(  # noqa: PLR0913 too many arguments
     external_dependencies_only: Optional[bool] = None,
     odoo_series_override: Optional[str] = None,
     odoo_version_override: Optional[str] = None,
-    post_version_strategy_override: Optional[str] = None,
+    post_version_strategy_override: Optional[PostVersionStrategyOverrideStr] = None,
     precomputed_metadata_file: Optional[Path] = None,
 ) -> Dict[str, Any]:
     addon_dir = tmp_path / addon_dir_name
@@ -554,7 +555,7 @@ def test_git_post_version(
     tmp_path: Path,
     manifest_version: str,
     post_commits: int,
-    post_version_strategy_override: Optional[str],
+    post_version_strategy_override: Optional[PostVersionStrategyOverrideStr],
     expected_version: str,
 ) -> None:
     addon_dir = _make_git_addon(
@@ -589,7 +590,7 @@ def test_git_post_version_uncommitted_change(
     tmp_path: Path,
     manifest_version: str,
     post_commits: int,
-    post_version_strategy_override: str,
+    post_version_strategy_override: PostVersionStrategyOverrideStr,
     expected_version: str,
 ) -> None:
     addon_dir = _make_git_addon(
@@ -618,7 +619,7 @@ def test_git_post_version_uncommitted_change(
 )
 def test_git_post_version_bad_manifest_in_history(
     tmp_path: Path,
-    post_version_strategy_override: str,
+    post_version_strategy_override: PostVersionStrategyOverrideStr,
 ) -> None:
     addon_dir = _make_git_addon(tmp_path, manifest_version="16.0.1.1.0")
     addon_dir.joinpath("__manifest__.py").write_text(
@@ -651,7 +652,7 @@ def test_git_post_version_bad_manifest_in_history(
 )
 def test_git_post_version_good_manifest_in_history(
     tmp_path: Path,
-    post_version_strategy_override: str,
+    post_version_strategy_override: PostVersionStrategyOverrideStr,
 ) -> None:
     addon_dir = _make_git_addon(tmp_path, manifest_version="16.0.1.1.0")
     addon_dir.joinpath("__manifest__.py").write_text(
@@ -679,7 +680,7 @@ def test_git_post_version_good_manifest_in_history(
 )
 def test_git_post_version_no_manifest_in_history(
     tmp_path: Path,
-    post_version_strategy_override: str,
+    post_version_strategy_override: PostVersionStrategyOverrideStr,
 ) -> None:
     addon_dir = _make_git_addon(tmp_path, manifest_version="16.0.1.1.0")
     subprocess.check_call(["git", "rm", "__manifest__.py"], cwd=addon_dir)