Highlights

Standalone Activities (Public Preview)

Support for Standalone Activities is now in Public Preview.
Telemetry support has been expanded with improved OpenTracingClientInterceptor and a new OpenTracingActivityClientInterceptor.

Standalone Nexus Operations (Experimental)

This release adds NexusClient interface for interacting with Nexus services outside of workflows. The NexusServiceClient
generic interface can be used to execute operations of a specific Nexus service in a type-safe manner.

GZIP transport-level compression

Client connections now use GZIP transport-level gRPC compression by default.
Use setGrpcCompression(GrpcCompression.NONE) when building ServiceStubsOptions to disable it.

Continue-as-New USE_RAMPING_VERSION versioning behaviour

Continue-as-New now supports USE_RAMPING_VERSION as an initial versioning behavior.
It pins the workflow to its task queue's Ramping Version at start time, ignoring the workflow's Target Version.

Activity cancellation without heartbeating

Activities can receive cancellation requests without waiting for a heartbeat response if running against a recent enough version of the server.
You can use the ActivityExecutionContext.getCancellationToken() method to detect such cancellations when not using the heartbeat() API.

Additional worker shutdown options

Enabling WorkerOptions.Builder.setAllowActivityHeartbeatDuringShutdown removes the limitation on activity heartbeats during
graceful worker shutdown, matching the behavior of other SDKs. Note that this will make it impossible to detect graceful shutdown
via ActivityWorkerShutdownException, so if the detection is desired, an alternative method is needed.

WorkerFactoryOptions.Builder.setShutdownCheckInterval can be used to speed up worker shutdown in certain testing scenarios.
Changing this setting in production environment is discouraged.

What's Changed

2026-05-04 - 5a765b1 - CaN USE_RAMPING_VERSION versioning behaviour (#2868)
2026-05-07 - 20afdcb - Expose Nexus Endpoint on Nexus Info (#2837)
2026-05-14 - 1e110b2 - Fixed a bug with spaces in WorkflowIds when creating links in the UI. (#2874)
2026-05-18 - b19042b - Expose ShutdownManager poll interval via WorkerFactoryOptions (#2876)
2026-05-19 - 1386d4b - Add banner like other SDKs have (#2877)
2026-05-19 - 73560d3 - remove stale nightly tps omes test (#2879)
2026-05-19 - caba351 - Upgrade cloud-api to v0.16.0 (#2873)
2026-05-21 - 7a8e684 - Improve CONTRIBUTING guide and streamline local dev requirements (#2871)
2026-05-22 - 44bb603 - Shutdown task loss prevention (#2820)
2026-05-22 - d45886c - Fixed flaky test WorkerFactoryRegistryTest.testRandomOrder (#2886)
2026-05-27 - 187421b - Upgrade temporal-api to v1.62.12 (#2892)
2026-05-27 - f71f93b - remove dead omes job (#2891)
2026-06-01 - e947cc2 - Add history hints to workflow task started attributes (#2865)
2026-06-02 - 3ed4985 - Add cooldown on dependabot config (#2888)
2026-06-08 - 4d53976 - Wait for MARKER_RECORDED to fire version callback on replay (#2821)
2026-06-10 - 62a7f08 - Fix flaky test NexusWorkflowTest.testNexusOperationTimeout_AfterStart (#2908)
2026-06-11 - 27cfa7d - Add Temporal Nexus Operation Handler (#2842)
2026-06-11 - 5f25aad - Standalone operations for Nexus (#2872)
2026-06-12 - 2bc7d9b - Use constants for all failure_reason metrics (#2914)
2026-06-12 - c9c4bdc - Add tests for temporal-kotlin extension APIs (#2905)
2026-06-15 - 3c2d938 - Standalone Activities start delay (#2906)
2026-06-15 - 7390e05 - feat(extstore): add initial extstore types (#2900)
2026-06-15 - 78d0fee - Add backoff start for CAN (#2913)
2026-06-15 - f3edb10 - Add GZIP compression defaulting to on (#2911)
2026-06-16 - a1b6fff - Add OpenTracing interceptor for standalone activities (#2909)
2026-06-16 - aeac5b1 - Grant explicit actions:read to features reusable-workflow caller (#2919)
2026-06-18 - 8d8ca1b - Nexus Signal links (#2889)
2026-06-18 - 8e5ee33 - Support Standalone Activity client in temporal-testing (#2916)
2026-06-18 - dae5e0b - Add option to let activities heartbeat during worker shutdown (#2903)
2026-06-22 - 85e12a3 - feat(otel): add tracing for startWithUpdate. fixes #2620. (#2925)
2026-06-23 - e976113 - Implement nexus-based activity cancels (#2917)