diff --git a/stubs/peewee/METADATA.toml b/stubs/peewee/METADATA.toml
index 5fc0f5088484..fd90d18f0b87 100644
--- a/stubs/peewee/METADATA.toml
+++ b/stubs/peewee/METADATA.toml
@@ -1,4 +1,4 @@
-version = "4.0.0"
+version = "4.0.1"
 upstream_repository = "https://github.com/coleifer/peewee"
 # We're not providing stubs for all playhouse modules right now
 # https://github.com/python/typeshed/pull/11731#issuecomment-2065729058
diff --git a/stubs/peewee/peewee.pyi b/stubs/peewee/peewee.pyi
index 13f5b1922710..4473cb766d91 100644
--- a/stubs/peewee/peewee.pyi
+++ b/stubs/peewee/peewee.pyi
@@ -6,7 +6,7 @@ from collections.abc import Callable, Generator, Iterable, Iterator
 from datetime import datetime
 from decimal import Decimal
 from types import TracebackType
-from typing import Any, ClassVar, Final, Literal, NamedTuple, TypeVar
+from typing import Any, ClassVar, Final, Literal, NamedTuple, TypeVar, overload
 from typing_extensions import Self
 from uuid import UUID
 
@@ -20,6 +20,7 @@ basestring = str
 long = int
 izip_longest = itertools.zip_longest
 
+_T = TypeVar("_T")
 _VT = TypeVar("_VT")
 _F = TypeVar("_F", bound=Callable[..., Any])
 
@@ -400,6 +401,7 @@ class SQL(ColumnBase):
     def __sql__(self, ctx): ...
 
 def Check(constraint, name=None): ...
+def Default(value) -> SQL: ...
 
 class Function(ColumnBase):
     no_coerce_functions: ClassVar[set[str]]
@@ -849,7 +851,9 @@ class SqliteDatabase(Database):
     server_version: Incomplete
     truncate_table: bool
     nulls_ordering: bool
-    def __init__(self, database, regexp_function: bool = False, *args, **kwargs) -> None: ...
+    def __init__(
+        self, database, pragmas=None, regexp_function: bool = False, rank_functions: bool = False, *args, **kwargs
+    ) -> None: ...
     returning_clause: Incomplete
     def init(self, database, pragmas=None, timeout: int = 5, returning_clause=None, **kwargs) -> None: ...
     def pragma(self, key, value=..., permanent: bool = False, schema: str | None = None): ...
@@ -902,7 +906,20 @@ class SqliteDatabase(Database):
     def to_timestamp(self, date_field) -> Cast: ...
     def from_timestamp(self, date_field) -> Function: ...
 
-class Psycopg2Adapter:
+class _BasePsycopgAdapter:
+    isolation_levels: dict[int, str]
+    isolation_levels_inv: dict[str, int]
+    def __init__(self) -> None: ...
+    @overload
+    def isolation_level_int(self, isolation_level: str) -> int: ...
+    @overload
+    def isolation_level_int(self, isolation_level: _T) -> _T: ...
+    @overload
+    def isolation_level_str(self, isolation_level: int) -> str: ...
+    @overload
+    def isolation_level_str(self, isolation_level: _T) -> _T: ...
+
+class Psycopg2Adapter(_BasePsycopgAdapter):
     json_type: Incomplete
     jsonb_type: Incomplete
     cast_json_case: bool
@@ -916,7 +933,7 @@ class Psycopg2Adapter:
     def is_connection_closed(self, conn) -> bool: ...
     def extract_date(self, date_part, date_field) -> Function: ...
 
-class Psycopg3Adapter:
+class Psycopg3Adapter(_BasePsycopgAdapter):
     json_type: Incomplete
     jsonb_type: Incomplete
     cast_json_case: bool
@@ -973,6 +990,7 @@ class PostgresqlDatabase(Database):
     def from_timestamp(self, date_field) -> Function: ...
     def get_noop_select(self, ctx): ...
     def set_time_zone(self, timezone) -> None: ...
+    def set_isolation_level(self, isolation_level: int | str) -> None: ...
 
 class MySQLDatabase(Database):
     field_types: Incomplete
@@ -1037,7 +1055,7 @@ class _savepoint(_callable_context_manager):
     quoted_sid: Incomplete
     def __init__(self, db, sid=None) -> None: ...
     def commit(self, begin: bool = True) -> None: ...
-    def rollback(self) -> None: ...
+    def rollback(self, begin: bool = True) -> None: ...
     def __enter__(self) -> Self: ...
     def __exit__(
         self, exc_type: type[BaseException] | None, exc_val: BaseException | None, exc_tb: TracebackType | None
@@ -1854,6 +1872,7 @@ __all__ = [
     "DateField",
     "DateTimeField",
     "DecimalField",
+    "Default",
     "DeferredForeignKey",
     "DeferredThroughModel",
     "DJANGO_MAP",