1.20.0
Worker Heartbeating (Public Preview)
This release adds a new feature called Worker Heartbeating. This feature spins up a single nexus-only worker per Client/Namespace/Task Queue in the background and periodically sends some basic metrics over to server for all of the workers registered on the same Client/Namespace/Task Queue.
Server version 1.29.1 and newer supports this feature. This feature will be enabled by default, although this currently requires a server dynamic config flag, --dynamic-config-value frontend.WorkerHeartbeatsEnabled=true to enable. Currently, the only way to interact with this new data is to also enable the flag --dynamic-config-value frontend.ListWorkersEnabled=true, then use CLI commands temporal worker list and temporal worker describe to query the data. If heartbeating is enabled with a server version older or with the config flag off, a single warning log Worker heartbeating configured for runtime, but server version does not support it. on worker startup will emit.
Highlights
- Core was upgraded from 682d441 to 45b1d7e.
Runtimeuse across forks now eagerly fails, making it fail in a more obvious way. Specifically, using aRuntimefrom a different process ID will now eagerly fail.
Breaking changes
- Core crate names have changed, see https://github.com/temporalio/sdk-core/pull/1034 for more details. If users are directly referencing these crate names, like for setting log levels, they will need to be updated to the new names.
Specific Changes
2025-11-17 - 5d1630d - Nexus task cancellation (#1204)
2025-11-17 - ceb7058 - Prevent Runtime use over forks (#1208)
2025-11-21 - 3fd1c7e - Fix up plugin readme (#1211)
2025-11-24 - 6d2924b - Add Summary to Nexus operations (#1219)
2025-11-24 - 77f2346 - use sys.stdlib_module_names in restrictions. Move dynamic import warning to only apply to non-passed through modules (#1222)
2025-11-25 - b5001f9 - Update Core, configure worker types, send plugin names to Core (#1157)