diff --git a/amaranth-stubs b/amaranth-stubs
index c92fccb8c..886d1b3b5 160000
--- a/amaranth-stubs
+++ b/amaranth-stubs
@@ -1 +1 @@
-Subproject commit c92fccb8c04dbb7633ad99cdf6f10ec58e5b38a5
+Subproject commit 886d1b3b5cb1aa268b9f59168918765a11b5b45f
diff --git a/requirements.txt b/requirements.txt
index 4596816f7..7d70b711d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
 ./amaranth-stubs/  # can't use -e -- pyright doesn't see the stubs then :(
-amaranth-yosys==0.38.0.0.post88
-git+https://github.com/amaranth-lang/amaranth@6d65dc1366da2313e8e6a77d5093ddd6acdec8aa
+amaranth-yosys==0.40.0.0.post100
+git+https://github.com/amaranth-lang/amaranth@9bd536bbf96b07720d6e4a8709b30492af8ddd13
 dataclasses-json==0.6.3
diff --git a/test/transactron/test_assign.py b/test/transactron/test_assign.py
index dab0225bf..7398570fa 100644
--- a/test/transactron/test_assign.py
+++ b/test/transactron/test_assign.py
@@ -3,7 +3,7 @@
 from amaranth import *
 from amaranth.lib import data
 from amaranth.lib.enum import Enum
-from amaranth.hdl._ast import ArrayProxy, Slice
+from amaranth.hdl._ast import ArrayProxy, SwitchValue, Slice
 
 from transactron.utils._typing import MethodLayout
 from transactron.utils import AssignType, assign
@@ -143,11 +143,14 @@ def test_assign_a(self, name, layout1: MethodLayout, layout2: MethodLayout, atyp
         self.assertIs_AP(alist[0].rhs, self.extrr(rhs).a)
 
     def assertIs_AP(self, expr1, expr2):  # noqa: N802
-        if isinstance(expr1, ArrayProxy) and isinstance(expr2, ArrayProxy):
+        expr1 = Value.cast(expr1)
+        expr2 = Value.cast(expr2)
+        if isinstance(expr1, SwitchValue) and isinstance(expr2, SwitchValue):
             # new proxies are created on each index, structural equality is needed
-            self.assertIs(expr1.index, expr2.index)
-            assert len(expr1.elems) == len(expr2.elems)
-            for x, y in zip(expr1.elems, expr2.elems):
+            self.assertIs(expr1.test, expr2.test)
+            assert len(expr1.cases) == len(expr2.cases)
+            for (px, x), (py, y) in zip(expr1.cases, expr2.cases):
+                self.assertEqual(px, py)
                 self.assertIs_AP(x, y)
         elif isinstance(expr1, Slice) and isinstance(expr2, Slice):
             self.assertIs_AP(expr1.value, expr2.value)
diff --git a/transactron/lib/metrics.py b/transactron/lib/metrics.py
index 6f63e27e9..78f5c5e53 100644
--- a/transactron/lib/metrics.py
+++ b/transactron/lib/metrics.py
@@ -175,6 +175,10 @@ def add_registers(self, regs: list[HwMetricRegister]):
     def metrics_enabled(self) -> bool:
         return DependencyContext.get().get_dependency(HwMetricsEnabledKey())
 
+    # To restore hashability lost by dataclass subclassing
+    def __hash__(self):
+        return object.__hash__(self)
+
 
 class HwCounter(Elaboratable, HwMetric):
     """Hardware Counter
diff --git a/transactron/utils/assign.py b/transactron/utils/assign.py
index 7b0b3eab7..4257d2df6 100644
--- a/transactron/utils/assign.py
+++ b/transactron/utils/assign.py
@@ -217,7 +217,7 @@ def has_explicit_shape(val: ValueLike):
             if valuelike_shape(lhs) != valuelike_shape(rhs):
                 raise ValueError(
                     "Shapes not matching: lhs: {} {} rhs: {} {}".format(
-                        valuelike_shape(lhs), lhs, valuelike_shape(rhs), rhs
+                        valuelike_shape(lhs), repr(lhs), valuelike_shape(rhs), repr(rhs)
                     )
                 )