3.6

3.6.12 - It’s not a feature, it’s a bug!

Released on January 20, 2026

Enhancements ➕➕

• Add httpx.ConnectError to client retry exceptions by @joshuastagner in #20276

Bug Fixes 🐞

• Add build=False documentation to flow.deploy guide by @devin-ai-integration[bot] in #20269
• fix: display error details nicely in work-pool create command by @devin-ai-integration[bot] in #20277
• fix: remove CANCELLED from EnforceCancellingToCancelledTransition to allow retrying cancelled flows by @zzstoatzz in #20275
• Add retry logic to PrefectEventSubscriber.__aenter__() for initial connections by @devin-ai-integration[bot] in #20295
• fix: convert dynamic_key to str in sync client’s create_task_run by @zzstoatzz in #20302
• Fix wait() timeout not being respected when using WatcherThreadCancelScope by @devin-ai-integration[bot] in #20257

Development & Tidiness 🧹

• migrate RemoteFileSystem and SMB from @sync_compatible to @async_dispatch by @zzstoatzz in #20230
• Migrate notification blocks from @sync_compatible to @async_dispatch by @zzstoatzz in #20258
• Fix Devin flaky tests workflow API integration by @desertaxle in #20272
• Add GitHub Actions workflow to trigger Devin.ai on test failures by @desertaxle in #20255

Documentation 📓

• Add release notes for integration packages by @desertaxle in #20266

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.11…3.6.12

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3.6.11 - It’s my generation, baby

Released on January 15, 2026

This release introduces prefect sdk generate a new CLI command that generates fully-typed, custom Python SDKs from the deployments in your workspace or self-hosted server, making it easy to trigger your deployments from other workflows with confidence.

To see how it works, check out the Prefect docs. This functionality is currently in beta, so try it out and open a GitHub issue if you have feedback!

New Features 🎉

• Add prefect sdk generate CLI command for generating custom deployment SDKs from existing deployments by @desertaxle in #20150, #20158, #20167, #20172, #20173

Enhancements ➕➕

• Add JSON output to prefect variable ls CLI command by @xeniumcode in #20192
• Add JSON output to prefect global-concurrency-limit ls CLI command by @xeniumcode in #20194
• Add JSON output to prefect artifact CLI commands by @xeniumcode in #20193
• Add JSON output to prefect block ls CLI command by @xeniumcode in #20195
• Add JSON output to prefect block type ls CLI command by @xeniumcode in #20196
• Add JSON output to prefect deployment schedule CLI commands by @xeniumcode in #20197
• Add JSON output to prefect deployment CLI commands by @xeniumcode in #20198
• Migrate pause, suspend, resume, and run_input from @sync_compatible to @async_dispatch by @devin-ai-integration[bot] in #20178
• Add force parameter to ChangeFlowRunState and flow_run_id Jinja filter by @zzstoatzz in #20112
• Link automation.action.* events to automation.triggered event by @chrisguidry in #20227
• Add DISABLED to client DeploymentStatus enum for Cloud compatibility by @chrisguidry in #20244

Bug Fixes 🐞

• Fix flow run cancellation handling bugs by @joshuastagner in #20143
• Fix race condition in filesystem lease storage with atomic writes by @devin-ai-integration[bot] in #20153
• Add task keys to docket calls in API handlers to prevent duplicate execution by @desertaxle in #20210
• Support ISO 8601 duration strings for interval schedules in prefect.yaml by @zzstoatzz in #20238
• Disable Docket result storage to prevent memory bloat by @desertaxle in #20253
• Preserve the updated column value of deployments when marking them as ready by @vkrot-innio in #19936

Development & Tidiness 🧹

• Add arun_deployment and replace @sync_compatible with @async_dispatch by @desertaxle in #20160
• Patch correct method in test_concurrency_respects_timeout by @devin-ai-integration[bot] in #20185
• Fix flaky test by reducing slot_decay_per_second to prevent race condition by @devin-ai-integration[bot] in #20208
• Remove incorrect docstrings from CLI ls commands by @zzstoatzz in #20206
• Add Claude command frontmatter by @zzstoatzz in #20224
• Enable multi-checker type safety tests with mypy, pyright, and ty by @zzstoatzz in #20159
• Migrate concurrency/v1 from @sync_compatible to @async_dispatch by @zzstoatzz in #20225
• Migrate blocks/core.py from @sync_compatible to @async_dispatch by @devin-ai-integration[bot] in #20226
• Stale item cleanup enhancements by @bdalpe in #20145
• Add plan label to exclude from release notes by @zzstoatzz in #20182
• Auto-label PRs that touch plans/ directory by @zzstoatzz in #20183
• Disable migrations and block registration for multi-worker test by @devin-ai-integration[bot] in #20179
• Fix plan label to only apply when all changed files are in plans/ by @desertaxle in #20207

Documentation 📓

• Add ECS base job template customization guide by @zzstoatzz in #20249
• Fix MDX parsing error in events CLI documentation by @desertaxle in #20252
• Add documentation for prefect sdk generate CLI by @desertaxle in #20241

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.10…3.6.11

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3.6.10 - Five Bugs Walked Into A Bar And None Of Them Left

Released on January 08, 2026

Enhancements ➕➕

• Add prefect automation update CLI command by @devin-ai-integration[bot] in #20118
• Add upserting global concurrency limit decay by @cbrown1234 in #20124

Bug Fixes 🐞

• Fix AttributeError in Consumer.cleanup() for non-memory brokers by @devin-ai-integration[bot] in #20089
• Fix exception_to_crashed_state_sync failing without async backend by @zzstoatzz in #20139
• Fix MockValSer serialization error with StateDetails by @zzstoatzz in #20127
• Resolve race condition in compound trigger evaluation by @desertaxle in #20106
• Fix AttributeError for functools.partial hooks in Runner by @devin-ai-integration[bot] in #20136

Development & Tidiness 🧹

• Add UISettings model for /ui-settings endpoint by @desertaxle in #20103
• Fix flaky test_concurrency_respects_timeout test by @devin-ai-integration[bot] in #20138
• Update @prefecthq/prefect-ui-library to version 3.14.8 by @marvin-robot in #20147
• Run integration tests against PostgreSQL to prevent CI timeouts by @devin-ai-integration[bot] in #20080
• Use correct apt version syntax for git in Dockerfile by @devin-ai-integration[bot] in #20094

Documentation 📓

• Link to MCP server security FAQ by @zzstoatzz in #20120
• Fix broken ECS worker deployment guide links by @devin-ai-integration[bot] in #20119
• Clarify that base job template variables must be referenced in job_configuration by @zzstoatzz in #20133

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.9…3.6.10

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3.6.9 - Auld Lang Sync

Released on December 31, 2025

New Features 🎉

• Add worker-side cancellation for pending flow runs by @joshuastagner in #20022

Enhancements ➕➕

• Add JSON schema for prefect.yaml files by @zzstoatzz in #19996
• Send entrypoint pip install errors to Prefect logs by @jakekaplan in #20058
• Run read and count queries concurrently in paginate endpoints by @zzstoatzz in #20049

Bug Fixes 🐞

• Preserve symlinks in get_directory instead of following them by @majiayu000 in #19993
• Fix GitRepository name parameter preservation in pull step conversion by @devin-ai-integration[bot] in #20004
• Add explicit ruamel.yaml.clib dependency to fix Docker builds by @zzstoatzz in #20068

Development & Tidiness 🧹

• Update @prefecthq/prefect-ui-library to version 3.14.5 by @marvin-robot in #20003
• Add GitHub Actions workflow for UI v2 E2E tests by @devin-ai-integration[bot] in #20042

Documentation 📓

• Add link to Python AI Conference by @aaazzam in #20054

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.8…3.6.9

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3.6.8 - On Exception! On Timeout! On Error and Failure! 🦌

Released on December 24, 2025

New Features 🎉

• Add prefect flow-run retry command by @desertaxle in #19858

Enhancements ➕➕

• Add url property to server-side ReceivedEvent for automation templates by @devin-ai-integration[bot] in #19851

Bug Fixes 🐞

• Add timeout to Docket worker shutdown by @desertaxle in #19940
• Prevent dictionary mutation during iteration in preprocess_schema by @zzstoatzz in #19946
• Allow string form_data in CustomWebhookNotificationBlock by @zzstoatzz in #19953
• Bump pydocket version and remove background worker shutdown timeout by @desertaxle in #19969
• Fix TASK_SOURCE cache policy for remote execution with cloudpickle by @desertaxle in #19926

Development & Tidiness 🧹

• Run lint, build, and test in parallel for ui-v2 checks by @devin-ai-integration[bot] in #19884
• Fix docker deploy integration test failing due to uv import by @desertaxle in #19899
• Update kickoff-release schedule from Monday to Thursday by @devin-ai-integration[bot] in #19930

Documentation 📓

• Add security considerations to Prefect MCP server guide by @zzstoatzz in #19875
• Document AWS IAM role assumption by @seanpwlms in #19963

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.7…3.6.8

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3.6.7 - LoopService #OpenToWork: 3+ Years Experience Looping

Released on December 18, 2025

Enhancements ➕➕

• Add support for AWS IAM authentication for PostgreSQL database by @alaminopu in #19580
• Add generic typing support for Variable.get method by @devin-ai-integration[bot] in #19764
• Convert late_runs service to Docket perpetual function by @zzstoatzz in #19722
• Convert repossessor service to Docket perpetual function by @zzstoatzz in #19739
• Convert foreman service to Docket perpetual function by @zzstoatzz in #19741
• Convert telemetry service to Docket perpetual function by @zzstoatzz in #19754
• Convert scheduler and proactive triggers to Docket, remove LoopService by @zzstoatzz in #19756

Bug Fixes 🐞

• Update broken links in creating-automations docs by @devin-ai-integration[bot] in #19759
• Silence retryable SQLite lock errors from docket.worker logger by @devin-ai-integration[bot] in #19772
• Exclude unset grace_period_seconds from deployment concurrency_options by @zzstoatzz in #19784
• Correct docket_url setting path to server.docket.url by @zzstoatzz in #19791
• Fix Mattermost bot name issue by @tre-ert in #19780
• Restore netloc-based credential formatting for YAML deployments by @zzstoatzz in #19873

Development & Tidiness 🧹

• Add @chrisguidry as a CODEOWNER by @zzstoatzz in #19738

Documentation 📓

• Add negative matching documentation for automation triggers by @chrisguidry in #19760

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.6…3.6.7

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3.6.6 - The Eternal Docket of the Spotless Server

Released on December 08, 2025

Enhancements ➕➕

• Add client-side configuration for deployment concurrency grace period by @devin-ai-integration[bot] in #19489
• Add PostgreSQL search_path support via settings by @devin-ai-integration[bot] in #19620
• Add memory safeguards to event persister service by @desertaxle in #19651
• Add perpetual services infrastructure and convert cancellation_cleanup to perpetual Docket task by @zzstoatzz in #19715
• Convert pause_expirations service to perpetual Docket task by @zzstoatzz in #19719

Bug Fixes 🐞

• Prevent uvloop from setting global event loop policy in healthcheck by @zzstoatzz in #19660
• Clarify result_storage usage with @task and @flow decorators by @devin-ai-integration[bot] in #19671
• Exclude DEFAULT cache policy from triggering automatic persist_result by @devin-ai-integration[bot] in #19673
• Remove return type annotation from settings serializer to fix OpenAPI schema by @zzstoatzz in #19616
• Use history_interval_seconds as parameter name in OpenAPI schema by @desertaxle in #19659

Development & Tidiness 🧹

• Turn off dependabot for Vue UI package updates by @desertaxle in #19636
• Add weekly release kickoff workflow by @desertaxle in #19661
• Migrate prefect.input.actions from sync_compatible to async_dispatch by @zzstoatzz in #19632
• Remove auto-generate docs workflow by @desertaxle in #19665

Documentation 📓

• Fix incorrect Dockerfile example in “Deploy via Python” guide by @desertaxle in #19653

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.5…3.6.6

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3.6.5 - Batch Me If You Can

Released on December 04, 2025

Enhancements ➕➕

• Raise if event is too big by @jakekaplan in #19531
• Support Path objects in result_storage parameter by @zzstoatzz in #19533
• Hide “Join the Community” in air-gapped deployments by @zzstoatzz in #19540
• Parametrize xreadgroup batch size in consumer and add EventPersister service setting by @saschwartz in #19545
• Parametrize xautoclaim batch size by @saschwartz in #19557
• Parametrize TaskRunRecorder and Trigger service message read batch size by @saschwartz in #19559
• Add Slack GovCloud (slack-gov.com) webhook support to SlackWebhook block by @devin-ai-integration[bot] in #19565
• Support dot-delimited syntax for job_variables in workers by @devin-ai-integration[bot] in #19619
• Add client-side caching for concurrency limits by @devin-ai-integration[bot] in #19625

Bug Fixes 🐞

• Support username:password auth for self-hosted BitBucket instances by @zzstoatzz in #19516
• Optimize /api/task_runs/count endpoint performance by @naaa760 in #19548
• Fix docker compose file in self hosted docs by @rodeyfeld in #19551
• Fix performance issues with sync tasks on Windows by @desertaxle in #19595
• Fix dead thread hang by @zzstoatzz in #19601
• Allow Jinja templates in trigger enabled field during YAML loading by @zzstoatzz in #19610
• Fix compatibility with fastapi==0.123.7 by @desertaxle in #19626
• Allow EC2 task definitions to omit launchType for capacity providers by @zzstoatzz in #19630

Integrations & Dependencies 🤝

• Update sucrase to remove vulnerable glob dependency by @zzstoatzz in #19599

Development & Tidiness 🧹

• Add timeout to worker teardown to prevent test flakes by @zzstoatzz in #19465
• Update CODEOWNERS by @desertaxle in #19578
• Pin pytest-asyncio to fix 3.10 client tests by @desertaxle in #19609
• Fix flakes in TestReadTaskRunCountsByState::test_returns_all_state_types by @desertaxle in #19612

Documentation 📓

• Add per-worker task concurrency example by @zzstoatzz in #19541
• Improve database maintenance documentation and examples by @zzstoatzz in #19604
• Fix YAML key for Bitbucket repository by @desertaxle in #19607
• Add Google Tag Manager integration to docs by @zzstoatzz in #19629

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.4…3.6.5

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3.6.4 - No Deployment Left Unparametrized

Released on November 21, 2025

Bug Fixes 🐞

• fix: preserve event template parameters in deployment triggers by @zzstoatzz in #19504
• Fix truncating log behavior by @jakekaplan in #19496

Integrations & Dependencies 🤝

• Chore: Bump ui library by @znicholasbrown in #19492

Documentation 📓

• docs: Add migration note about unmapped mutable objects by @zzstoatzz in #19494

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.3…3.6.4

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3.6.3 - That’s JSON Bourne

Released on November 19, 2025

Enhancements ➕➕

• Add -o json output option to prefect flow-run ls command by @devin-ai-integration[bot] in #19484
• fix: allow pause_flow_run() to pause parent flow when called from task by @zzstoatzz in #19457

Bug Fixes 🐞

• Use acquisition service pattern for lease-based concurrency slots by @bunchesofdonald in #19451
• fix: respect subflow attributes (log_prints, result_storage) when running inside task by @zzstoatzz in #19450
• fix: defer forward reference resolution in ValidatedFunction by @zzstoatzz in #19452
• fix: validate deployment triggers after templating so jinja-based booleans work, should close #19348 by @iclectic in #19414
• fix: show detailed validation errors for top-level prefect.yaml fields by @zzstoatzz in #19468
• Clamp denied_slots decay rate to match retry-after calculation by @bunchesofdonald in #19466
• Fix: Enable parameter type checking for @task decorator by @zzstoatzz in #19459

Development & Tidiness 🧹

• add —build-arg to dev build-image command to allow direct passing of… by @conrade-ctc in #19473

Documentation 📓

• Add database cleanup example with human/AI approval by @zzstoatzz in #19456

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.2…3.6.3

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3.6.2 - The Missing Link

Released on November 13, 2025

Enhancements ➕

• Add causal link from automation action events to triggering events by @zzstoatzz in #19426

Bug Fixes 🐞

• cap retry-after for concurrency limits to prevent excessive delays by @zzstoatzz in #19428
• accept numeric values for PREFECT_API_SERVICES_LATE_RUNS_AFTER_SECONDS by @zzstoatzz in #19434
• add work_queue_id to DeploymentResponse by @zzstoatzz in #19417

Development & Tidiness 🧹

• correct GitHub Actions conditional syntax in integration release workflow by @zzstoatzz in #19439

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.1…3.6.2

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3.6.1 - Pop, Lock it, Docket

Released on November 10, 2025

Enhancements ➕

• Add logfire sampling configuration and fix boolean env var handling by @zzstoatzz in #19383

Bug Fixes 🐞

• Fix interactive deploy CLI selecting wrong flow when opting out by @zzstoatzz in #19392
• Fix deployment.parameters in nested flows using ContextVars by @zzstoatzz in #19366

Integrations & Dependencies 🤝

• Upgrade pydocket to stable 0.13.0 release by @zzstoatzz in #19401

Documentation 📓

• Add client methods for querying events via REST API by @zzstoatzz in #19382

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.0…3.6.1

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3.6.0 - Throw it on the docket and we’ll get to it in a jiffy

This release adds pydocket, a background task system, to replace FastAPI’s background_tasks. Background tasks now include automatic retries and can optionally use Redis as a backing layer for enhanced durable execution.

Released on November 07, 2025

Enhancements ➕➕

• Replace FastAPI background_task usage with pydocket by @desertaxle in #19377
• Emit events for deployment pull step execution by @zzstoatzz in #19339

Bug Fixes 🐞

• Fix import order dependency and circular import issues by @zzstoatzz in #19344
• Fix deployment.parameters in subprocess flows by @zzstoatzz in #19331
• Fix misleading pyright error when calling async task with wrong argument types by @zzstoatzz in #19327
• Fix EventsWorker singleton leak in prefect_test_harness by @zzstoatzz in #19343
• Fix run_deployment execution graph display when called from tasks by @desertaxle in #19361
• Fix automation deletion deadlock by enforcing consistent lock ordering by @zzstoatzz in #19369

Integrations & Dependencies 🤝

• Update prefect-ui-library to latest version by @znicholasbrown in #19350

Development & Tidiness 🧹

• Remove legacy settings imports from CLI by @desertaxle in #19353
• Clean up root directory by @zzstoatzz in #19355
• Replace Optional with pipe syntax in _trim_traceback function by @devin-ai-integration[bot] in #19358
• Auto-close superseded documentation PRs by @zzstoatzz in #19357
• Add @chrisguidry as a CODEOWNER by @desertaxle in #19368
• Sync UI v2 OpenAPI schema with node v20.19.0 by @zzstoatzz in #19373
• Migrate RedisStorageContainer from sync_compatible to async_dispatch by @devin-ai-integration[bot] in #19363

Documentation 📓

• Add Pulumi section to Infrastructure as Code documentation by @bdalpe in #19352
• Fix link in ECS worker docs by @mattiamatrix in #19364

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.5.0…3.6.0

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