reflex-dev/reflex · error · DynamicComponentMissingLibraryError

Component must have a library to bundle.

Error message

Component must have a library to bundle.

What it means

After unpickling, the stored substate schema string is compared with the current class's `_to_schema()`. A mismatch raises StateSchemaMismatchError, guarding against unpickling state written by a different app/schema version.

Source

Thrown at packages/reflex-base/src/reflex_base/components/dynamic.py:51

    bundled[:] = _default_bundled_libraries()


def bundle_library(component: Union["Component", str]):
    """Bundle a library with the component.

    Args:
        component: The component to bundle the library with.

    Raises:
        DynamicComponentMissingLibraryError: Raised when a dynamic component is missing a library.
    """
    bundled = RegistrationContext.ensure_context().bundled_libraries
    if isinstance(component, str):
        bundled.append(format_library_name(component))
        return
    if component.library is None:
        msg = "Component must have a library to bundle."
        raise DynamicComponentMissingLibraryError(msg)
    bundled.append(format_library_name(component.library))


def load_dynamic_serializer():
    """Load the serializer for dynamic components."""
    # Causes a circular import, so we import here.
    from reflex_base.components.component import Component

    @serializer
    def make_component(component: Component) -> str:
        """Generate the code for a dynamic component.

        Args:
            component: The component to generate code for.

        Returns:
            The generated code
        """

View on GitHub (pinned to 45b8ed5ab7)

Solutions

1. Flush the affected redis keys (or bump the redis db / token prefix) so fresh state is generated
2. Keep schema changes backward compatible by avoiding renames/removals of existing fields
3. Catch StateSchemaMismatchError and recreate default state for the token

Example fix

// before
state = await StateRoot.deserialize(data=pickled)
// after
try:
    state = StateRoot.deserialize(data=pickled)
except StateSchemaMismatchError:
    state = StateRoot()

try:
    state = StateRoot.deserialize(data=pickled)
except StateSchemaMismatchError:
    state = StateRoot()  # reset token state after schema change

When it happens

Trigger: Loading pickled state (from redis or custom storage) where fields/substates changed since it was serialized — renamed vars, added/removed substates, reordered fields.

Common situations: Deploying a new version with changed State classes while users' tokens persist in redis; local dev against a redis instance holding old-schema state.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• Deserialized state is not an instance of BaseState, cannot p
• ChildrenTypeError(component=cls.__name__, child=child)
• Do not override _add_style directly. Use add_style instead.
• The component `{comp_name}` only allows the components: {val
• Undefined library for NoSSRComponent

AI-assisted analysis of reflex-dev/reflex@45b8ed5ab7 (2026-08-28). Data as JSON: /api/errors/b711525925191cf5. Report an issue: GitHub.