diff --git a/pytype/matcher.py b/pytype/matcher.py
index 964730a63..c18e12881 100644
--- a/pytype/matcher.py
+++ b/pytype/matcher.py
@@ -456,12 +456,17 @@ def match_var_against_type(self, var, other_type, subst, view):
 
   def _match_type_param_against_type_param(self, t1, t2, subst, view):
     """Match a TypeVar against another TypeVar."""
-    if t1.full_name == "typing.Self" and not t1.bound:
-      # We're matching a Self instance before it's been bound to its containing
-      # class. We know it should be bound but not to what, so `Any` is the best
-      # we can do.
-      t1 = t1.copy()
-      t1.bound = self.ctx.convert.unsolvable
+    if t1.full_name == "typing.Self":
+      if t2.full_name == "typing.Self":
+        # Self always matches itself. We check for this explicitly because Self
+        # instances may have their bounds set to incompatible classes.
+        return subst
+      elif not t1.bound:
+        # We're matching a Self instance before it's been bound to its
+        # containing class. We know it should be bound but not to what, so `Any`
+        # is the best we can do.
+        t1 = t1.copy()
+        t1.bound = self.ctx.convert.unsolvable
     if t2.constraints:
       assert not t2.bound  # constraints and bounds are mutually exclusive
       # We only check the constraints for t1, not the bound. We wouldn't know
@@ -1461,7 +1466,7 @@ def _match_dict_against_typed_dict(
     for k, v in left.pyval.items():
       if k not in fields:
         continue
-      typ = abstract_utils.get_atomic_value(fields[k])
+      typ = fields[k]
       match_result = self.compute_one_match(v, typ)
       if not match_result.success:
         bad.append((k, match_result.bad_matches))
diff --git a/pytype/output.py b/pytype/output.py
index 3d8ed112a..1babd3486 100644
--- a/pytype/output.py
+++ b/pytype/output.py
@@ -1016,10 +1016,8 @@ def _typed_dict_to_def(self, node, v, name):
       keywords.append(("total", pytd.Literal(False)))
     bases = (pytd.NamedType("typing.TypedDict"),)
     constants = []
-    for k, var in v.props.fields.items():
-      typ = pytd_utils.JoinTypes(
-          self.value_instance_to_pytd_type(node, p, None, set(), {})
-          for p in var.data)
+    for k, val in v.props.fields.items():
+      typ = self.value_instance_to_pytd_type(node, val, None, set(), {})
       if v.props.total and k not in v.props.required:
         typ = pytd.GenericType(pytd.NamedType("typing.NotRequired"), (typ,))
       elif not v.props.total and k in v.props.required:
diff --git a/pytype/overlays/dataclass_overlay.py b/pytype/overlays/dataclass_overlay.py
index 5cbde5358..33a356c58 100644
--- a/pytype/overlays/dataclass_overlay.py
+++ b/pytype/overlays/dataclass_overlay.py
@@ -97,7 +97,7 @@ def decorate(self, node, cls):
         continue
       kind = ""
       init = True
-      kw_only = False
+      kw_only = sticky_kwonly
       assert typ
       if match_classvar(typ):
         continue
@@ -112,8 +112,8 @@ def decorate(self, node, cls):
           field = orig.data[0]
           orig = field.default
           init = field.init
-          if self.ctx.python_version >= (3, 10):
-            kw_only = sticky_kwonly if field.kw_only is None else field.kw_only
+          if field.kw_only is not None:
+            kw_only = field.kw_only
 
       if orig and orig.data == [self.ctx.convert.none]:
         # vm._apply_annotation mostly takes care of checking that the default
diff --git a/pytype/overlays/typed_dict.py b/pytype/overlays/typed_dict.py
index 46a6ec569..8cee96637 100644
--- a/pytype/overlays/typed_dict.py
+++ b/pytype/overlays/typed_dict.py
@@ -2,7 +2,7 @@
 
 import dataclasses
 
-from typing import Any, Dict, Optional, Set
+from typing import Dict, Optional, Set
 
 from pytype.abstract import abstract
 from pytype.abstract import abstract_utils
@@ -34,7 +34,7 @@ class TypedDictProperties:
   """Collection of typed dict properties passed between various stages."""
 
   name: str
-  fields: Dict[str, Any]
+  fields: Dict[str, abstract.BaseValue]
   required: Set[str]
   total: bool
 
@@ -48,27 +48,15 @@ def optional(self):
 
   def add(self, k, v, total):
     """Adds key and value."""
-    values = []
-    all_requiredness = set()
-    for value in v.data:
-      req = _is_required(value)
-      if req is None:
-        values.append(value)
-        all_requiredness.add(None)
-      elif isinstance(value, abstract.ParameterizedClass):
-        values.append(value.formal_type_parameters[abstract_utils.T])
-        all_requiredness.add(req)
-      else:
-        values.append(value.ctx.convert.unsolvable)
-        all_requiredness.add(req)
-    if (len(all_requiredness) == 1 and
-        (requiredness := next(iter(all_requiredness))) is not None):
-      final_v = v.program.NewVariable(values, [], v.program.entrypoint)
-      required = requiredness
+    req = _is_required(v)
+    if req is None:
+      value = v
+    elif isinstance(v, abstract.ParameterizedClass):
+      value = v.formal_type_parameters[abstract_utils.T]
     else:
-      final_v = v
-      required = total
-    self.fields[k] = final_v  # pylint: disable=unsupported-assignment-operation
+      value = v.ctx.convert.unsolvable
+    required = total if req is None else req
+    self.fields[k] = value  # pylint: disable=unsupported-assignment-operation
     if required:
       self.required.add(k)
 
@@ -122,7 +110,12 @@ def _extract_args(self, args):
         name=name, fields={}, required=set(), total=total)
     # Force Required/NotRequired evaluation
     for k, v in fields.items():
-      props.add(k, v, total)
+      try:
+        value = abstract_utils.get_atomic_value(v)
+      except abstract_utils.ConversionError:
+        self.ctx.errorlog.ambiguous_annotation(self.ctx.vm.frames, v.data, k)
+        value = self.ctx.convert.unsolvable
+      props.add(k, value, total)
     return props
 
   def _validate_bases(self, cls_name, bases):
@@ -182,8 +175,14 @@ def make_class(self, node, bases, f_locals, total):
         ordering=classgen.Ordering.FIRST_ANNOTATE,
         ctx=self.ctx)
     for k, local in cls_locals.items():
-      assert local.typ
-      props.add(k, local.typ, total)
+      var = local.typ
+      assert var
+      try:
+        typ = abstract_utils.get_atomic_value(var)
+      except abstract_utils.ConversionError:
+        self.ctx.errorlog.ambiguous_annotation(self.ctx.vm.frames, var.data, k)
+        typ = self.ctx.convert.unsolvable
+      props.add(k, typ, total)
 
     # Process base classes and generate the __init__ signature.
     self._validate_bases(cls_name, bases)
@@ -207,7 +206,7 @@ def make_class_from_pyi(self, cls_name, pytd_cls):
         name=name, fields={}, required=set(), total=total)
 
     for c in pytd_cls.constants:
-      typ = self.ctx.convert.constant_to_var(c.type)
+      typ = self.ctx.convert.constant_to_value(c.type)
       props.add(c.name, typ, total)
 
     # Process base classes and generate the __init__ signature.
@@ -239,8 +238,7 @@ def _make_init(self, props):
     sig = function.Signature.from_param_names(
         f"{props.name}.__init__", props.fields.keys(),
         kind=pytd.ParameterKind.KWONLY)
-    sig.annotations = {k: abstract_utils.get_atomic_value(v)
-                       for k, v in props.fields.items()}
+    sig.annotations = dict(props.fields)
     sig.defaults = {k: self.ctx.new_unsolvable(self.ctx.root_node)
                     for k in props.optional}
     return abstract.SimpleFunction(sig, self.ctx)
@@ -256,8 +254,7 @@ def _new_instance(self, container, node, args):
   def instantiate_value(self, node, container):
     args = function.Args(())
     for name, typ in self.props.fields.items():
-      args.namedargs[name] = self.ctx.join_variables(
-          node, [t.instantiate(node) for t in typ.data])
+      args.namedargs[name] = typ.instantiate(node)
     return self._new_instance(container, node, args)
 
   def instantiate(self, node, container=None):
@@ -301,7 +298,7 @@ def _check_str_key(self, name):
 
   def _check_str_key_value(self, node, name, value_var):
     self._check_str_key(name)
-    typ = abstract_utils.get_atomic_value(self.fields[name])
+    typ = self.fields[name]
     bad = self.ctx.matcher(node).compute_one_match(value_var, typ).bad_matches
     for match in bad:
       self.ctx.errorlog.annotation_type_mismatch(
diff --git a/pytype/overriding_checks.py b/pytype/overriding_checks.py
index bc3afc686..eb629dcdd 100644
--- a/pytype/overriding_checks.py
+++ b/pytype/overriding_checks.py
@@ -414,7 +414,8 @@ def is_subtype(this_type, that_type):
     """Return True iff this_type is a subclass of that_type."""
     if this_type == ctx.convert.never:
       return True  # Never is the bottom type, so it matches everything
-    this_type_instance = this_type.instantiate(ctx.root_node, None)
+    this_type_instance = this_type.instantiate(
+        ctx.root_node, container=abstract_utils.DUMMY_CONTAINER)
     return matcher.compute_one_match(this_type_instance, that_type).success
 
   check_result = (
diff --git a/pytype/tests/test_dataclasses.py b/pytype/tests/test_dataclasses.py
index 7a09cfbc1..8c46e2697 100644
--- a/pytype/tests/test_dataclasses.py
+++ b/pytype/tests/test_dataclasses.py
@@ -761,6 +761,26 @@ class A:
         def __init__(self, a1: int, a3: int, *, a2: int = ...) -> None: ...
     """)
 
+  @test_utils.skipBeforePy((3, 10), "KW_ONLY is new in 3.10")
+  def test_kwonly_and_nonfield_default(self):
+    ty = self.Infer("""
+      import dataclasses
+      @dataclasses.dataclass
+      class C:
+        _: dataclasses.KW_ONLY
+        x: int = 0
+        y: str
+    """)
+    self.assertTypesMatchPytd(ty, """
+      import dataclasses
+      @dataclasses.dataclass
+      class C:
+        x: int = ...
+        y: str
+        _: dataclasses.KW_ONLY
+        def __init__(self, *, x: int = ..., y: str) -> None: ...
+    """)
+
   def test_star_import(self):
     with self.DepTree([("foo.pyi", """
       import dataclasses
diff --git a/pytype/tests/test_flax_overlay.py b/pytype/tests/test_flax_overlay.py
index 40b57fff0..b80602680 100644
--- a/pytype/tests/test_flax_overlay.py
+++ b/pytype/tests/test_flax_overlay.py
@@ -266,6 +266,34 @@ def __init__(
           def replace(self: _TBaz, **kwargs) -> _TBaz: ...
       """)
 
+  @test_utils.skipBeforePy((3, 10), "KW_ONLY is new in 3.10")
+  def test_kwonly(self):
+    with test_utils.Tempdir() as d:
+      self._setup_linen_pyi(d)
+      ty = self.Infer("""
+        import dataclasses
+        from flax import linen as nn
+        class C(nn.Module):
+          _: dataclasses.KW_ONLY
+          x: int = 0
+          y: str
+      """, pythonpath=[d.path])
+    self.assertTypesMatchPytd(ty, """
+      import dataclasses
+      from flax import linen as nn
+      from typing import Any, TypeVar
+
+      _TC = TypeVar('_TC', bound=C)
+
+      @dataclasses.dataclass
+      class C(nn.module.Module):
+        x: int = ...
+        y: str
+        _: dataclasses.KW_ONLY
+        def __init__(self, *, x: int = ..., y: str, name: str = ..., parent: Any = ...) -> None: ...
+        def replace(self: _TC, **kwargs) -> _TC: ...
+    """)
+
 
 if __name__ == "__main__":
   test_base.main()
diff --git a/pytype/tests/test_typed_dict.py b/pytype/tests/test_typed_dict.py
index 5f89d6646..302b391d9 100644
--- a/pytype/tests/test_typed_dict.py
+++ b/pytype/tests/test_typed_dict.py
@@ -385,6 +385,14 @@ def f() -> TD:
           return __any_object__
       """)
 
+  def test_duplicate_key(self):
+    self.CheckWithErrors("""
+      from typing_extensions import TypedDict
+      class TD(TypedDict):  # invalid-annotation
+        x: int
+        x: str
+    """)
+
 
 class TypedDictFunctionalTest(test_base.BaseTest):
   """Tests for typing.TypedDict functional constructor."""
@@ -458,6 +466,16 @@ class X(TypedDict, total=False):
         name: str
     """)
 
+  def test_ambiguous_field_type(self):
+    self.CheckWithErrors("""
+      from typing_extensions import TypedDict
+      if __random__:
+        v = str
+      else:
+        v = int
+      X = TypedDict('X', {'k': v})  # invalid-annotation
+    """)
+
 
 _SINGLE = """
   from typing import TypedDict
diff --git a/pytype/tests/test_typing_self.py b/pytype/tests/test_typing_self.py
index 61d5410a6..6f88ec37e 100644
--- a/pytype/tests/test_typing_self.py
+++ b/pytype/tests/test_typing_self.py
@@ -281,6 +281,17 @@ def f(self) -> Self:
           return self
     """)
 
+  def test_signature_compatibility(self):
+    self.Check("""
+      from typing_extensions import Self
+      class Parent:
+        def add(self, other: Self) -> Self:
+          return self
+      class Child(Parent):
+        def add(self, other: Self) -> Self:
+          return self
+    """)
+
 
 class SelfPyiTest(test_base.BaseTest):
   """Tests for typing.Self usage in type stubs."""