diff --git a/electrolytes/__init__.py b/electrolytes/__init__.py
index 76dcdda..5f4c94c 100644
--- a/electrolytes/__init__.py
+++ b/electrolytes/__init__.py
@@ -1,10 +1,11 @@
+from __future__ import annotations
+
 import pkgutil
 from collections.abc import Collection, Iterator, Mapping, Sequence
 from contextlib import ContextDecorator, suppress
 from functools import cached_property, singledispatchmethod
 from pathlib import Path
-from types import TracebackType
-from typing import Annotated, Optional
+from typing import TYPE_CHECKING, Annotated
 from warnings import warn
 
 from filelock import FileLock
@@ -18,11 +19,20 @@
 )
 from typer import get_app_dir
 
+if TYPE_CHECKING:
+    import sys
+    from types import TracebackType
+
+    if sys.version_info >= (3, 11):
+        from typing import Self
+    else:
+        from typing_extensions import Self
+
 __version__ = "0.4.6"
 
 
 class Constituent(BaseModel, populate_by_name=True, frozen=True):
-    id: Optional[int] = None
+    id: int | None = None
     name: str
     u_neg: Annotated[
         list[float], Field(alias="uNeg")
@@ -112,7 +122,7 @@ def _pka_lengths(cls, v: list[float], info: ValidationInfo) -> list[float]:
 
     @field_validator("neg_count", "pos_count", mode="before")
     @classmethod
-    def _counts(cls, v: Optional[int], info: ValidationInfo) -> int:
+    def _counts(cls, v: int | None, info: ValidationInfo) -> int:
         assert isinstance(info.field_name, str)
         if v is None:
             v = len(info.data[f"u_{info.field_name[:3]}"])
@@ -122,7 +132,7 @@ def _counts(cls, v: Optional[int], info: ValidationInfo) -> int:
         return v
 
     @model_validator(mode="after")
-    def _pkas_not_increasing(self) -> "Constituent":
+    def _pkas_not_increasing(self) -> Constituent:
         pkas = [*self.pkas_neg, *self.pkas_pos]
 
         if not all(x >= y for x, y in zip(pkas, pkas[1:])):
@@ -136,7 +146,7 @@ def _pkas_not_increasing(self) -> "Constituent":
 
 
 def _load_constituents(
-    data: bytes, context: Optional[dict[str, str]] = None
+    data: bytes, context: dict[str, str] | None = None
 ) -> list[Constituent]:
     return _StoredConstituents.validate_json(data, context=context)["constituents"]
 
@@ -194,7 +204,7 @@ def _save_user_constituents(self) -> None:
             self._user_constituents_file.write_bytes(data)
         self._user_constituents_dirty = False
 
-    def __enter__(self) -> "_Database":
+    def __enter__(self) -> Self:
         if not self._user_constituents_lock.is_locked:
             self._invalidate_user_constituents()
         self._user_constituents_lock.acquire()
@@ -203,9 +213,9 @@ def __enter__(self) -> "_Database":
 
     def __exit__(
         self,
-        exc_type: Optional[type[BaseException]],
-        exc_value: Optional[BaseException],
-        traceback: Optional[TracebackType],
+        exc_type: type[BaseException] | None,
+        exc_value: BaseException | None,
+        traceback: TracebackType | None,
     ) -> None:
         try:
             if (
diff --git a/electrolytes/__main__.py b/electrolytes/__main__.py
index 0fd7a34..6bb3192 100644
--- a/electrolytes/__main__.py
+++ b/electrolytes/__main__.py
@@ -1,4 +1,6 @@
-from typing import Annotated, Optional
+from __future__ import annotations
+
+from typing import Annotated
 
 import typer
 
@@ -135,7 +137,7 @@ def add(
 @app.command()
 def info(
     names: Annotated[
-        Optional[list[str]],
+        list[str] | None,
         typer.Argument(help="Component names", autocompletion=complete_name),
     ] = None,
 ) -> None:
@@ -192,7 +194,7 @@ def info(
 def ls(
     *,
     user: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--user/--default", help="List only user-defined/default components"
         ),
@@ -218,7 +220,7 @@ def rm(
     ],
     *,
     force: Annotated[
-        Optional[bool], typer.Option("-f", help="Ignore non-existent components")
+        bool | None, typer.Option("-f", help="Ignore non-existent components")
     ] = False,
 ) -> None:
     """Remove user-defined components from the database."""
@@ -243,7 +245,7 @@ def rm(
 def search(
     text: str,
     user: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--user/--default", help="Search only user-defined/default components"
         ),
diff --git a/pyproject.toml b/pyproject.toml
index 76dbbc2..8dfccac 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -41,6 +41,7 @@ dynamic = ["version"]
 lint = ["ruff"]
 typing = [
     "mypy==1.*",
+    "typing-extensions>=4,<5; python_version < '3.11'",
     "pytest>=7,<9",
 ]
 test = [