[WIP] Add experimental Event Groups support

CHANGELOG.md

@@ -20,6 +20,14 @@ to include examples, links to docs, or any other relevant information.
 
 ### Added
 
+- **Experimental**: Experimental support for _Event Groups_. **Event Groups** is a new form of
+  Workflow-level metadata that allows for improved visibility into a Workflow execution's history
+  by grouping logically related Events together based on user-defined or system-inferred criteria.
+  An event group is created using `workflow.create_event_group(label)`, then attach it either per
+  call (`workflow.start_activity(..., event_groups=[group])`) or ambiently to everything issued
+  inside `with group.scope():`. Each signal and update handler is also implicitly wrapped in a
+  group of its own. Requires a server that understands the Event Groups fields.
+
 ### Changed
 
 - System Nexus Signal-with-Start Workflow operations now use the typed

mise.toml

@@ -0,0 +1,7 @@
+[tools]
+python = "3.14.7"
+uv = "0.12.9"
+
+[settings]
+# Activate (and create if needed) the uv-managed .venv when entering the project
+python.uv_venv_auto = "create|source"

temporalio/worker/_interceptor.py

@@ -177,6 +177,7 @@ class ContinueAsNewInput:
     headers: Mapping[str, temporalio.api.common.v1.Payload]
     versioning_intent: VersioningIntent | None
     initial_versioning_behavior: ContinueAsNewVersioningBehavior | None
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None
     # The types may be absent
     arg_types: list[type] | None
 
@@ -231,6 +232,7 @@ class SignalChildWorkflowInput:
     args: Sequence[Any]
     child_workflow_id: str
     headers: Mapping[str, temporalio.api.common.v1.Payload]
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None = None
 
 
 @dataclass
@@ -243,6 +245,7 @@ class SignalExternalWorkflowInput:
     workflow_id: str
     workflow_run_id: str | None
     headers: Mapping[str, temporalio.api.common.v1.Payload]
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None = None
 
 
 @dataclass
@@ -263,6 +266,7 @@ class StartActivityInput:
     disable_eager_execution: bool
     versioning_intent: VersioningIntent | None
     summary: str | None
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None
     priority: temporalio.common.Priority
     # The types may be absent
     arg_types: list[type] | None
@@ -293,6 +297,7 @@ class StartChildWorkflowInput:
     versioning_intent: VersioningIntent | None
     static_summary: str | None
     static_details: str | None
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None
     priority: temporalio.common.Priority
     # The types may be absent
     arg_types: list[type] | None
@@ -313,6 +318,7 @@ class StartNexusOperationInput(Generic[InputT, OutputT]):
     cancellation_type: temporalio.workflow.NexusOperationCancellationType
     headers: Mapping[str, str] | None
     summary: str | None
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None = None
     output_type: type[OutputT] | None = None
 
     def __post_init__(self) -> None:
@@ -366,6 +372,7 @@ class StartLocalActivityInput:
     cancellation_type: temporalio.workflow.ActivityCancellationType
     headers: Mapping[str, temporalio.api.common.v1.Payload]
     summary: str | None
+    event_groups: Sequence[temporalio.workflow.EventGroup] | None
 
     # The types may be absent
     arg_types: list[type] | None

temporalio/worker/_workflow.py

@@ -694,6 +694,7 @@ def _create_workflow_instance(
             first_execution_run_id=init.first_execution_run_id,
             headers=dict(init.headers),
             namespace=self._namespace,
+            original_execution_run_id=init.original_execution_run_id or act.run_id,
             parent=parent,
             root=root,
             raw_memo=dict(init.memo.fields),