1.29.0

Notable Changes

Added

• Added experimental temporalio.workflow.signal_with_start_workflow, backed by
  generated system Nexus bindings for
  WorkflowService.SignalWithStartWorkflowExecution.
• Added OpenAI Agents plugin support for CustomTool dispatch, including lazy
  tool discovery through defer_loading.

Changed

• Client connections now use gzip transport-level gRPC compression by default.
  Pass grpc_compression=GrpcCompression.NONE to Client.connect or
  CloudOperationsClient.connect to disable it.

Breaking Changes

• StartWorkflowUpdateWithStartInput now owns the authoritative
  rpc_metadata and rpc_timeout fields for
  OutboundInterceptor.start_update_with_start_workflow. These fields were
  removed from the nested update-with-start input objects, so custom
  interceptors that accessed them there should read or update the top-level
  fields instead.

Fixed

• Fixed breakpoint() and pdb.set_trace() inside workflow code when a worker
  runs with debug_mode=True or TEMPORAL_DEBUG=1; sandboxed workflows without
  debug mode now get a clearer error pointing to debug_mode=True.

• Fixed start_update_with_start_workflow interceptor handling so RPC metadata
  and timeouts are forwarded to the underlying execute_multi_operation call.

• Fixed OpenAI Agents plugin streamed event serialization when pydantic had not
  yet built deferred schemas, and fixed terminal sandbox errors retrying
  forever.

• Removed the lazy-connect lock from the per-RPC hot path. It was previously
  acquired on every RPC, putting an event-loop-bound primitive on the hot path;
  it is now skipped once the client is connected. This reduces the client's
  coupling to the event loop it connected on, which can help when reusing a
  single long-lived Client across event loops or threads (e.g. the
  dedicated-loop pattern used with gevent/gunicorn and synchronous services).
  Note this does not make a Client fully thread- or loop-agnostic; reusing one
  long-lived loop is still the recommended pattern.

  SDK Core

  • 993de3fb deps: sync api_upstream subtree to temporal-api@6c8bd13 (#1293)
  • d0065e38 Rename master to main for API deps (#1309)
  • f57f6f06 fix(sdk): no longer expose raw proto for application error category (#1307)
  • 40d24ec8 bump version (#1317)
  • f1899d23 Add gzip compression by default with option to opt-out (#1310)
  • f43520e6 Add CHANGELOG and document the update process (#1315)
  • c5a6646e Update API Upstream to pull in WIT generation (#1320)

What's Changed

• Add CHANGELOG and document the update process by @cconstable in #1580
• Use ActivitySerializationContext when describing a Standalone Activity by @VegetarianOrc in #1583
• Build streamed OpenAI events before serializing them by @brianstrauch in #1586
• Update core submodule by @tconley1428 in #1590
• AI-249: Support CustomTool in OpenAI Agents plugin tool dispatch by @xumaple in #1570
• 💥 Fix interceptor contract inconsistency for start_update_with_start_workflow by @brucearctor in #1588
• Fix error message for tracer provider initialization by @tconley1428 in #1584
• System Nexus payload handling from WIT by @tconley1428 in #1572
• Gzip compression options by @Sushisource in #1587
• Fix pdb / breakpoint() hang in workflow code by @elidlocke in #1568
• Upgrade PyO3 to 0.29 by @tconley1428 in #1599
• Translate terminal sandbox errors to non-retryable ApplicationError by @xumaple in #1595
• Fix asyncio lock contention in client calls by @Sushisource in #1606
• Bump version to 1.29.0 by @tconley1428 in #1607

New Contributors

• @elidlocke made their first contribution in #1568

Full Changelog: 1.28.0...1.29.0

1.28.0

Experimental Releases

Strands Agents Plugin

This release adds a new Temporal Plugin for running Strands Agents inside Temporal Workflows. Model invocations, tool calls, and MCP tool calls are routed through Temporal Activities, so your agents get durable execution, retries, and timeouts for free.

Workflow Streams support for LangGraph

The LangGraph plugin can now durably stream node output to external consumers. Values written with langgraph.config.get_stream_writer() are published to a Workflow Streams topic.

Standalone Nexus Operations

Standalone Nexus Operations is experimental and currently only supported on pre-release versions of the dev server.

Added support for Standalone Nexus Operations, allowing clients to start and manage Nexus operations directly outside of a Workflow. Documentation, Samples, and instructions to request enablement in Temporal Cloud will be linked here when available.

⚠️ Possible Local Activity Behavioral Difference

This release includes a bugfix in the Core library that changes incorrect behavior that may have unintentionally worked previously. Specifically, local activities that start running, and continue running while their associated workflow was evicted from the cache, could possibly be "re-attached" to the workflow if it was recreated before they finished. This behavior was unsound. Now, any running local activities are invalidated when a workflow is evicted. This change was really only likely to be encountered if you were running with the workflow cache disabled, which we never recommend doing.

What's Changed

• Bump ruff to 0.15 and reformat by @brianstrauch in #1507
• Format LangSmith tracing env override test by @tconley1428 in #1531
• Fix swallowed CancelledError in start_child_workflow and Nexus operations (Issue #1445) by @yegorske50 in #1472
• Use LangSmith runtime override API instead of monkey-patching aio_to_thread by @xumaple in #1477
• (CI) Disable caching cargo binaries by @maciejdudko in #1537
• Refactor client module into package by @tconley1428 in #1530
• Remove exclude-newer-package option by @brianstrauch in #1529
• Refactor workflow.py into package by @tconley1428 in #1488
• Fix documentation link for Workflow Streams by @brianstrauch in #1536
• Integration test for Standalone Activities delayed-start by @eamsden in #1520
• Update banner url by @Sushisource in #1542
• Address Flake in test_workflow_history_info by @VegetarianOrc in #1545
• remove stale nightly tps omes test by @THardy98 in #1544
• Implement Standalone Nexus Operations by @VegetarianOrc in #1461
• Drop macos-intel from CI by @eamsden in #1553
• ci: key Rust cache on resolved Python version by @brianstrauch in #1554
• Enabled frontend.enableCancelWorkerPollsOnShutdown in tests by @tconley1428 in #1555
• Narrow overloads on the SANO client by @VegetarianOrc in #1552
• VLN-1341: remediate missing-dependency-cooldown by @picatz in #1551
• LangGraph streaming with workflow streams by @brianstrauch in #1500
• fix: call task.uncancel() after catching CancelledError in shield loops (Python 3.11+) by @brucearctor in #1523
• Expose JSON type converter unhandled sentinel type by @Lingavasan in #1556
• remove unused omes job by @THardy98 in #1559
• Tolerate OpenAI model schema drift in the agents payload converter by @brianstrauch in #1563
• Add Temporal Operation Handler by @VegetarianOrc in #1503
• Bump langsmith from 0.7.38 to 0.8.0 by @dependabot[bot] in #1521
• Add Strands Agents plugin (contrib) by @brianstrauch in #1539
• Update Core by @Sushisource in #1564
• Swap from TemporalNexus prefix to Temporal by @VegetarianOrc in #1569
• Passthrough _pydevd_bundle to sandbox when debug mode is enabled by @VegetarianOrc in #1249
• contrib/strands: add cache_tools toggle to TemporalMCPClient by @brianstrauch in #1571
• Add workflow cancellation reason by @Sushisource in #1574
• Bump litellm to 1.85.0 and openai-agents to 0.17.3 by @dependabot[bot] in #1478
• Add trusted publishing release workflow by @tconley1428 in #1575
• Include nexus-operation-token in Nexus callback headers by @VegetarianOrc in #1576
• Bump version to 1.28.0 by @tconley1428 in #1577

New Contributors

• @yegorske50 made their first contribution in #1472
• @brucearctor made their first contribution in #1523
• @Lingavasan made their first contribution in #1556

Core Changes

2026-04-28 - 0f2f1b4c - chore: feature cleanup (temporalio/sdk-rust#1236)
2026-04-28 - 6f7e7536 - Move Core-specific test utilities out of the Common crate (temporalio/sdk-rust#1237)
2026-04-29 - 21263fa1 - 💥 feat(sdk): failure converter + rich error types (temporalio/sdk-rust#1226)
2026-04-29 - 9747e978 - Update cloud-api protos to v0.14.0 (temporalio/sdk-rust#1240)
2026-04-29 - a9481aae - bump versions 0.4.0 (temporalio/sdk-rust#1241)
2026-04-30 - 87162f50 - chore: upgrade doc code to no_run (temporalio/sdk-rust#1242)
2026-05-01 - 3a6efc35 - Fix flaky shutdown test (temporalio/sdk-rust#1243)
2026-05-01 - 9d1bdf90 - fix(macros): drop anyhow dependency from workflow_methods expansion (temporalio/sdk-rust#1246)
2026-05-05 - a22517e4 - chore: remove unnecessary anyhow wrapping (temporalio/sdk-rust#1247)
2026-05-12 - c57f825f - Add grpc-status trailers to fake gRPC responses (temporalio/sdk-rust#1257)
2026-05-13 - 99d6b402 - chore: update readme to mention public preview (temporalio/sdk-rust#1262)
2026-05-14 - 2ed11c8e - Enforce minimum DNS resolution interval (temporalio/sdk-rust#1272)
2026-05-14 - 68665e50 - Bump windows test leg to 20 minutes (temporalio/sdk-rust#1270)
2026-05-14 - a0ad8769 - feat(dns): add DNS load balancer settings to C bridge (temporalio/sdk-rust#1267)
2026-05-14 - eac03fbc - Upgrade cloud-api to v0.15.0 (temporalio/sdk-rust#1253)
2026-05-15 - 3e6ca9ff - VLN-1346: fix missing-dependency-cooldown (temporalio/sdk-rust#1275)
2026-05-15 - 6d2045dd - Make TLS backend feature-selectable in sdk-core and client (temporalio/sdk-rust#1274)
2026-05-18 - 56a4737e - fix: retry transport-sourced Cancelled errors and count them in metrics (temporalio/sdk-rust#1269)
2026-05-18 - 72374ca1 - (CI) Disable caching cargo binaries (temporalio/sdk-rust#1278)
2026-05-18 - de25e0c8 - fix(sdk): no longer error on cancelling fired timer (temporalio/sdk-rust#1268)
2026-05-19 - 179d7608 - refactor(examples): extract saga compensation into a reusable Saga pattern (temporalio/sdk-rust#1279)
2026-05-19 - 68a9661f - build(deps): update ringbuf requirement from 0.4 to 0.5 (temporalio/sdk-rust#1285)
2026-05-19 - 6c4011d1 - Update README & add banner (temporalio/sdk-rust#1280)
2026-05-19 - d6cfb9c7 - build(deps): update lru requirement from 0.16 to 0.18 (temporalio/sdk-rust#1276)
2026-05-21 - 96e0be0f - Add uds support in channel creation (temporalio/sdk-rust#1288)
2026-05-21 - d58edd2d - Add activity execution interceptors (temporalio/sdk-rust#1277)
2026-05-26 - 3839fa94 - feat(client): support custom ServerCertVerifier in TlsOptions (temporalio/sdk-rust#1271)
2026-05-26 - 5aaabd10 - 💥 WASM Workflows (temporalio/sdk-rust#1239)
2026-05-26 - 5d9faa8d - chore(sdk): rename child_workflow -> start_child_workflow (https://github.com/temporalio/sdk-core/...

1.26.1

Fix for worker shutdown ordering

There was an issue with worker shutdown when the frontend.enableCancelWorkerPollsOnShutdown dynamic config flag is enabled on server. The issue was causing shutdown to stall until the full 30s worker shutdown timeout was hit, as server was waiting for a message that the SDK was not sending. This fixes the SDK to send the proper message, allowing shutdown to occur normally.

What's Changed

• [backport 1.26.1] Update core to pickup shutdown fix by @yuandrew in #1527

Full Changelog: 1.26.0...1.26.1

1.25.1

Fix for worker shutdown ordering

There was an issue with worker shutdown when the frontend.enableCancelWorkerPollsOnShutdown dynamic config flag is enabled on server. The issue was causing shutdown to stall until the full 30s worker shutdown timeout was hit, as server was waiting for a message that the SDK was not sending. This fixes the SDK to send the proper message, allowing shutdown to occur normally.

What's Changed

• [backport 1.25.1] Update core to pickup shutdown fix by @yuandrew in #1526

Full Changelog: 1.25.0...1.25.1

1.24.2

Bug Fixes

• Removed upper bound constraint on types-protobuf dependency (#1525). The previous ceiling (<5.29.1) could cause dependency conflicts for users on newer types-protobuf versions. The constraint now matches the protobuf range (>=3.20,<7.0.0).

What's Changed

• [backport] Remove ceiling for types-protobuf by @yuandrew in #1525

Full Changelog: 1.24.1...1.24.2

1.27.2

DNS Resolver Load Balancing Configuration

A new load balancing feature was added in temporalio/sdk-rust#1212 which has caused networking issues in certain networking setups. This is now disabled by default via the change listed below.

What's Changed

• Default DNS lb config to None by @THardy98 in #1518

1.27.1

DNS Resolver Load Balancing Configuration

A new load balancing feature was added in temporalio/sdk-rust#1212 which has caused networking issues in certain networking setups. That can now be disabled via DnsLoadBalancingConfig.

What's Changed

• Fix flaky pause_and_assert helper by @brianstrauch in #1493
• Fix flaky LangGraph timeout tests by @DABH in #1495
• feat(otel): remove span creation for saa operations that do not currently propagate tracing headers. by @cconstable in #1492
• CaN USE_RAMPING_VERSION versioning behaviour by @THardy98 in #1499
• Say 'client_region' in S3 diagnostics for clarity by @drewhoskins-temporal in #1494
• contrib/openai_agents: stream model events via Workflow Streams by @jssmith in #1497
• contrib/google_adk_agents: stream LlmResponse chunks via Workflow Streams by @jssmith in #1498
• Fix CI, bump openinference-instrumentation-google-adk to 0.1.11 by @brianstrauch in #1508
• AI-183: Respect LANGSMITH_TRACING env var in LangSmith plugin by @xumaple in #1509
• Fix minor API break from latest OpenAI Agents version by @tconley1428 in #1511
• Plumb through option for configuring DNS resolver by @Sushisource in #1501

Core Changes

None!

1.24.1

Fix for worker shutdown ordering

There was an issue with worker shutdown when the frontend.enableCancelWorkerPollsOnShutdown dynamic config flag is enabled on server. The issue was causing shutdown to stall until the full 30s worker shutdown timeout was hit, as server was waiting for a message that the SDK was not sending. This fixes the SDK to send the proper message, allowing shutdown to occur normally.

What's Changed

• Pick up shutdown fix cherry-pick for v1.24.0 by @yuandrew in #1516

Full Changelog: 1.24.0...1.24.1

1.27.0

💥 External Storage Reference Format Change (Experimental)

External storage reference event history format has been incompatibly changed from prerelease. New storage references are emitted in the new format starting with release. Support for the ability to retrieve references in the old format has been preserved. The prerelease format is deprecated and will be removed in a future release.

Workflow Streams

This release adds Workflow Streams, a public preview contrib library that gives a workflow a durable, offset-addressed event channel for keeping outside observers updated on workflow and activity progress. It's built on Temporal's existing signals, updates, and queries, with batching, exactly-once deduplication, topic filtering, and continue-as-new helpers layered on top. Intended uses are streaming UIs for long-running AI agents, status for in-flight payment or order processing, and progress for data pipelines. It is not for not ultra-low-latency cases like real-time voice.

What's Changed

• Harden flaky workflow tests by @tconley1428 in #1456
• Pin GitHub Actions and cap uv deps by @tconley1428 in #1458
• Implement is_running() for asyncio loop by @brianstrauch in #1463
• chore: Update and pin all GHA actions by @mjameswh in #1464
• Fix flaky OpenAI test timeouts by @DABH in #1466
• AI-60: Add summary_fn parameter to TemporalModel for dynamic activity summaries by @xumaple in #1451
• Add OTel tracing for standalone activities by @cconstable in #1471
• More TMPRL1104 logging details by @jmaeagle99 in #1469
• Fix external storage CaN test stability by @jmaeagle99 in #1454
• Fix race condition in test_update_payload_conversion by @brianstrauch in #1473
• Fix race condition in test_async_response by @brianstrauch in #1474
• Fix race condition in test_cancellation_type for TRY_CANCEL by @brianstrauch in #1475
• Extend Workflow timeout for test_customer_service_workflow by @brianstrauch in #1476
• Update sdk-core submodule to latest by @jmaeagle99 in #1481
• Add AI Foundations as CODEOWNERs of AI plugins by @donald-pinckney in #1482
• chore: update submodule to sdk-rust by @chris-olszewski in #1480
• AI-36: Add LangGraph plugin by @brianstrauch in #1448
• 💥 Use ExternalStorageReference protobuf message for payload references by @jmaeagle99 in #1486
• External storage: Improved debuggability for region problems. by @drewhoskins-temporal in #1487
• Add start_delay for SAA by @Sushisource in #1491
• Update Python and Cargo lockfiles by @tconley1428 in #1483
• Add Workflow Streams library by @jssmith in #1423

Core Changes

2026-04-10 - 08adc4a4 - feat(sdk): add typed continue as new (temporalio/sdk-rust#1209)
2026-04-14 - 00d3888a - feat(client): ergonomic workflow description (temporalio/sdk-rust#1215)
2026-04-14 - c78bfb67 - Support static_summary, static_details and current_details` in the Rust sdk (temporalio/sdk-rust#1208)
2026-04-14 - d24a6f77 - chore(ci): bump macos-intel timeout (temporalio/sdk-rust#1214)
2026-04-15 - d7ebff81 - Add DNS load balancing (temporalio/sdk-rust#1212)
2026-04-16 - 33b86805 - fix(sdk): normalize how user metadata is encoded (temporalio/sdk-rust#1216)
2026-04-16 - 33c6c5e2 - Optimize dependencies (temporalio/sdk-rust#1219)
2026-04-16 - 72d8c5d3 - Fix test broken on windows by fake server binding to ipv6 (temporalio/sdk-rust#1220)
2026-04-16 - 904f4793 - Remove unused parking lot send guard feature (temporalio/sdk-rust#1218)
2026-04-17 - 1e67b234 - chore: Update and pin all GHA actions (temporalio/sdk-rust#1222)
2026-04-20 - 9171aca4 - 💥 feat(sdk): enforce some activity to close timeout is set (temporalio/sdk-rust#1221)
2026-04-21 - 703fe6b2 - Fix NDE when multiple patches in a single WFT exceed SA's 2048-byte limit (temporalio/sdk-rust#1225)
2026-04-22 - 984da134 - Set WFT Failed cause on grpc message too large incidents (temporalio/sdk-rust#1229)
2026-04-23 - 64cb6ed2 - Shutdown rpc initiate shutdown (temporalio/sdk-rust#1224)
2026-04-24 - 6dd29f2d - chore: rename master -> main in docs/crates/workflows (temporalio/sdk-rust#1233)
2026-04-25 - 30c4a313 - bump versions to 0.3.0 (temporalio/sdk-rust#1235)
2026-04-26 - 2872b536 - Update upstream api to latest (temporalio/sdk-rust#1234)

New Contributors

• @brianstrauch made their first contribution in #1463
• @DABH made their first contribution in #1466
• @cconstable made their first contribution in #1471

Full Changelog: 1.26.0...1.27.0

1.26.0

OpenAI Agents SDK Sandbox Support

This release adds support for the OpenAI Agents SDK's SandboxAgent in Temporal workflows. All sandbox lifecycle and I/O operations (create, exec, read, write, PTY, etc.) are automatically routed through Temporal activities, making them durable and replayable. If an agent fails mid-execution, Temporal ensures it picks up right where it left off in its sandbox. To use it, pass sandbox clients (e.g. DaytonaSandboxClient) to OpenAIAgentsPlugin(sandbox_clients=...). This release also updates compatibility with the latest OpenAI Agents SDK.

Breaking Changes

2026-04-09 - 4f05fc58 - 💥 Record task latency even for WFT failures that were dropped (temporalio/sdk-rust#1207) - The temporal_workflow_task_execution_latency metric is slightly more inclusive than it was in the past, and it can now include some WFT failures that may previously have been omitted

What's Changed

• Add LangSmith tracing plugin for Temporal workflows by @xumaple in #1369
• Add namespace to Nexus operation info by @Quinn-With-Two-Ns in #1416
• Add LiteLlm + TemporalModel integration test by @xumaple in #1431
• AI-59: Mark LangSmith plugin as experimental by @xumaple in #1441
• AI-61: Strip unset None fields from ADK plugin payloads by @xumaple in #1442
• S3 Driver: Require hash algorithm and value in claim payloads by @jmaeagle99 in #1443
• Expose Nexus Endpoint in a Nexus Operation Handler by @Quinn-With-Two-Ns in #1437
• Feat/OpenAI agents plugin sandbox support by @JasonSteving99 in #1452

Core Changes

2026-04-06 - a4fc7933 - feat(sdk): env config (temporalio/sdk-rust#1195)
2026-04-06 - ef57d63f - Correctly convert default_versioning_behavior in C bridge (temporalio/sdk-rust#1199)
2026-04-08 - 1f6cfb6c - fix(core): add in scheme port if none present (temporalio/sdk-rust#1205)
2026-04-08 - 723c2836 - feat(sdk): add samples (temporalio/sdk-rust#1190)
2026-04-08 - d96a8d2f - Move CODEOWNERS under .github/ (temporalio/sdk-rust#1198)
2026-04-09 - 630e7795 - Make sure legacy queries are failed if gRPC message too large (temporalio/sdk-rust#1206)
2026-04-10 - b544f95d - Expose Nexus Endpoint in a Nexus Operation Handler (temporalio/sdk-rust#1211)

New Contributors

• @xumaple made their first contribution in #1369

Full Changelog: 1.25.0...1.26.0