diff --git a/hugr-py/src/hugr/__init__.py b/hugr-py/src/hugr/__init__.py
index a5aabf025..37ab22645 100644
--- a/hugr-py/src/hugr/__init__.py
+++ b/hugr-py/src/hugr/__init__.py
@@ -2,11 +2,23 @@
 representation.
 """
 
+from .hugr import Hugr
+from .node_port import Direction, InPort, Node, OutPort, Wire
+from .ops import Op
+from .tys import Kind, Type
+
+__all__ = [
+    "Hugr",
+    "Node",
+    "OutPort",
+    "InPort",
+    "Direction",
+    "Op",
+    "Kind",
+    "Type",
+    "Wire",
+]
+
 # This is updated by our release-please workflow, triggered by this
 # annotation: x-release-please-version
 __version__ = "0.5.0"
-
-
-def get_serialization_version() -> str:
-    """Return the current version of the serialization schema."""
-    return "live"
diff --git a/hugr-py/src/hugr/serialization/extension.py b/hugr-py/src/hugr/serialization/extension.py
index 337149f49..fd533e781 100644
--- a/hugr-py/src/hugr/serialization/extension.py
+++ b/hugr-py/src/hugr/serialization/extension.py
@@ -3,10 +3,8 @@
 import pydantic as pd
 from pydantic_extra_types.semantic_version import SemanticVersion
 
-from hugr import get_serialization_version
-
 from .ops import Value
-from .serial_hugr import SerialHugr
+from .serial_hugr import SerialHugr, serialization_version
 from .tys import (
     ConfiguredBaseModel,
     ExtensionId,
@@ -76,7 +74,7 @@ class Extension(ConfiguredBaseModel):
 
     @classmethod
     def get_version(cls) -> str:
-        return get_serialization_version()
+        return serialization_version()
 
 
 class Package(ConfiguredBaseModel):
@@ -85,4 +83,4 @@ class Package(ConfiguredBaseModel):
 
     @classmethod
     def get_version(cls) -> str:
-        return get_serialization_version()
+        return serialization_version()
diff --git a/hugr-py/src/hugr/serialization/serial_hugr.py b/hugr-py/src/hugr/serialization/serial_hugr.py
index 476d23efc..8ccb58f85 100644
--- a/hugr-py/src/hugr/serialization/serial_hugr.py
+++ b/hugr-py/src/hugr/serialization/serial_hugr.py
@@ -2,8 +2,6 @@
 
 from pydantic import ConfigDict, Field
 
-import hugr
-from hugr import get_serialization_version
 from hugr.node_port import NodeIdx, PortOffset
 
 from .ops import OpType
@@ -13,8 +11,14 @@
 Port = tuple[NodeIdx, PortOffset | None]
 Edge = tuple[Port, Port]
 
+
+def serialization_version() -> str:
+    """Return the current version of the serialization schema."""
+    return "live"
+
+
 VersionField = Field(
-    default_factory=get_serialization_version,
+    default_factory=serialization_version,
     title="Version",
     description="Serialisation Schema Version",
     frozen=True,
@@ -34,7 +38,9 @@ class SerialHugr(ConfiguredBaseModel):
 
     def to_json(self) -> str:
         """Return a JSON representation of the Hugr."""
-        self.encoder = f"hugr-py v{hugr.__version__}"
+        from hugr import __version__ as hugr_version
+
+        self.encoder = f"hugr-py v{hugr_version}"
         return self.model_dump_json()
 
     @classmethod
diff --git a/hugr-py/tests/serialization/test_basic.py b/hugr-py/tests/serialization/test_basic.py
index 0f8e9209f..ccf43ca90 100644
--- a/hugr-py/tests/serialization/test_basic.py
+++ b/hugr-py/tests/serialization/test_basic.py
@@ -1,11 +1,10 @@
-from hugr import get_serialization_version
-from hugr.serialization.serial_hugr import SerialHugr
+from hugr.serialization.serial_hugr import SerialHugr, serialization_version
 
 
 def test_empty():
     h = SerialHugr(nodes=[], edges=[])
     assert h.model_dump() == {
-        "version": get_serialization_version(),
+        "version": serialization_version(),
         "nodes": [],
         "edges": [],
         "metadata": None,
diff --git a/hugr-py/tests/serialization/test_extension.py b/hugr-py/tests/serialization/test_extension.py
index 9e03731d0..6d4425b7d 100644
--- a/hugr-py/tests/serialization/test_extension.py
+++ b/hugr-py/tests/serialization/test_extension.py
@@ -1,6 +1,5 @@
 from semver import Version
 
-from hugr import get_serialization_version
 from hugr.serialization.extension import (
     ExplicitBound,
     Extension,
@@ -9,7 +8,7 @@
     TypeDef,
     TypeDefBound,
 )
-from hugr.serialization.serial_hugr import SerialHugr
+from hugr.serialization.serial_hugr import SerialHugr, serialization_version
 from hugr.serialization.tys import (
     FunctionType,
     PolyFuncType,
@@ -75,7 +74,7 @@
 
 
 def test_extension():
-    assert get_serialization_version() == Extension.get_version()
+    assert serialization_version() == Extension.get_version()
     param = TypeParam(root=TypeTypeParam(b=TypeBound.Copyable))
 
     bound = TypeDefBound(root=ExplicitBound(bound=TypeBound.Copyable))
@@ -113,7 +112,7 @@ def test_extension():
 
 
 def test_package():
-    assert get_serialization_version() == Package.get_version()
+    assert serialization_version() == Package.get_version()
 
     ext = Extension(
         version=Version(0, 1, 0),