3.7

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3.7.8 - The flush must go on

Released on July 09, 2026 Enhancements ➕➕

• Format server-side validation errors for concurrency slot acquisition by @devin-ai-integration[bot] in #22470

Bug Fixes 🐞

• Keep TaskRunRecorder periodic flush alive when events are dropped by @zzstoatzz in #22441
• Fix Windows permission error on git pull in runner storage by @devin-ai-integration[bot] in #22447
• Fix RRULE schedule anchor computed in UTC but interpreted as local time by @devin-ai-integration[bot] in #22456
• Reconnect events client from time-based checkpoint when connection is lost by @ZaeemRiaz in #22451
• Reject prefect api requests passing both --root and --account by @devin-ai-integration[bot] in #22462
• Differentiate HTTP 401 and 403 worker-channel upgrade failures by @devin-ai-integration[bot] in #22469

Development & Tidiness 🧹

• Loop until suspended in external-suspension integration test by @devin-ai-integration[bot] in #22466
• Add tests for untested functions in utilities.math by @eeshsaxena in #22438

Documentation 📓

• Replace legacy PREFECT_API_DATABASE_* examples with PREFECT_SERVER_DATABASE_* names by @devin-ai-integration[bot] in #22471
• Clarify AI contribution expectations by @desertaxle in #22023
• Clarify pull steps run before module-path entrypoint imports by @github-actions[bot] in #22402
• Fix parameter name mismatches in docstrings by @eeshsaxena in #22435

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.7…3.7.8

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3.7.7 - Don’t put that work pool configuration in your mouth. It’s stale.

Released on July 02, 2026 Enhancements ➕➕

• Accept a single step mapping in prefect.yaml action sections by @devin-ai-integration[bot] in #22403

Bug Fixes 🐞

• Fix set_working_directory relative path resolution in workspace resolver by @devin-ai-integration[bot] in #22392
• Run pull steps for module-path entrypoints when loading flow from flow run by @Abdulrehman-PIAIC80387 in #22376
• Fix UI version redirect leaking internal host behind reverse proxy by @devin-ai-integration[bot] in #22406
• Reconcile stale work-pool snapshots on worker heartbeat by @devin-ai-integration[bot] in #22429
• Send workspace resolver pull step logs to the API by @jakekaplan in #22432

Documentation 📓

• Fix typo in documentation about task result handling by @alastairtree in #22389
• Align Docker deployment examples with current step contract by @devin-ai-integration[bot] in #22400
• Add contextual menu to docs.json for copy and view markdown by @devin-ai-integration[bot] in #22401
• Fix Airflow migration typo by @devin-ai-integration[bot] in #22416
• Clarify rate limit documentation based on community feedback by @devin-ai-integration[bot] in #22413
• Update security issue reporting instructions by @desertaxle in #22356

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.6…3.7.7

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3.7.6 - You can only be Late once

Released on June 25, 2026 Bug Fixes 🐞

• Return PrefectFutureList from Task.map when deferred=True by @devin-ai-integration[bot] in #22355
• Fix race condition in UI static directory creation with multiple workers by @devin-ai-integration[bot] in #22363
• Raise clear error when FlowRun/TaskRun passed as task argument by @devin-ai-integration[bot] in #22352
• Prevent duplicate Late state transitions in MarkLateRuns by @Abdulrehman-PIAIC80387 in #22316
• Quote -q and -p args separately in work-queue create output by @devin-ai-integration[bot] in #22350

Development & Tidiness 🧹

• Widen timing tolerance in lease TTL test to prevent CI flakiness by @devin-ai-integration[bot] in #22328
• Fix flaky test_dispatches_cleanup_message_and_sends_ack_result by @devin-ai-integration[bot] in #22347

Documentation 📓

• Add deployment naming recommendations to concepts page by @devin-ai-integration[bot] in #22335
• Use canonical PREFECT_SERVER_SERVICES_SCHEDULER_* env vars in schedules page by @devin-ai-integration[bot] in #22337
• Bump mdxify to >=0.2.42, drop empty API-ref stubs by @zzstoatzz in #22339
• Append /api to self-hosted PREFECT_API_URL in systemd guide by @devin-ai-integration[bot] in #22342
• Use canonical PREFECT_SERVER_DATABASE_* env vars in Windows guide by @devin-ai-integration[bot] in #22343
• Regenerate API refs with mdxify >=0.2.45 (drop empty stubs) by @zzstoatzz in #22344
• Add redirects for removed SDK stubs by @zzstoatzz in #22349
• Use canonical PREFECT_WORKER_* defaults in healthchecks guide by @devin-ai-integration[bot] in #22351
• Document CANCELLING timeout that auto-transitions stuck flow runs to CANCELLED by @github-actions[bot] in #22305
• Note that Redis Cluster URLs are not yet supported in self-hosted setup by @github-actions[bot] in #22370
• Use schedules consistently in prefect.yaml guide and add deletion note by @devin-ai-integration[bot] in #22364
• Add dependent parameter form example by @zzstoatzz in #22383

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.5…3.7.6

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3.7.5 - No run left CANCELLING

Released on June 18, 2026 Enhancements ➕➕

• Add cancelling timeout cleanup producer by @desertaxle in #22238
• Add backend observability for worker channel and cleanup queue by @devin-ai-integration[bot] in #22310

Bug Fixes 🐞

• Fix pending task runs in flow run graph by @devin-ai-integration[bot] in #22287
• Add index on event_resources(occurred) for vacuum performance by @devin-ai-integration[bot] in #22250
• Fix FastAPI 0.137 compatibility — skip route deletion when router is referenced by @devin-ai-integration[bot] in #22277
• Degrade events WebSocket on transient connection failures by @yukiyan in #22241
• Declare ESCAPE character in LIKE expressions for SQLite compatibility by @devin-ai-integration[bot] in #22264
• Snapshot block registry before iterating in auto-registration by @devin-ai-integration[bot] in #22297
• Avoid subflow tracking key collisions by @zzstoatzz in #22286
• Preserve IANA timezone names in RRuleSchedule.from_rrule() by @devin-ai-integration[bot] in #22232
• Handle RecursionError in Flow.serialize_parameters by @chuqCTC in #22245
• Prevent SSRF via remote $ref in JSON schema validation by @chrisguidry in #22252
• URL-encode credentials in asyncpg LISTEN/NOTIFY DSN by @chuqCTC in #22089
• Fix profile inspect --output json emitting invalid JSON for active profile by @devin-ai-integration[bot] in #22317

Development & Tidiness 🧹

• Add “context deadline exceeded” to transient Docker build error patterns by @devin-ai-integration[bot] in #22266
• Use retry_asserts for flaky automation notification test by @devin-ai-integration[bot] in #22246
• Fix stale EventLoopThread globals after fork causing subprocess deadlocks by @devin-ai-integration[bot] in #22308
• Run db_vacuum maintenance queries without the API statement timeout by @zzstoatzz in #22291
• Support AnyIO 4.14 task group interface by @zzstoatzz in #22309
• Bump runtime uv image pins to 0.11.21 by @jakekaplan in #22265
• Migrate CI workflows to prefect-ci-bot trust-tier Apps by @jamiezieziula in #22288

Documentation 📓

• Document Cloud-only features and fix the Cloud badge by @mitchnielsen in #22229
• Add user-facing versioning and compatibility page by @mitchnielsen in #22228
• Document programmatic flow run cancellation by @zzstoatzz in #22243
• Fix deployment name format in schedule creation guide by @devin-ai-integration[bot] in #22284
• Align zombie-flow detection guide with current heartbeat defaults by @devin-ai-integration[bot] in #22285
• Document lifecycle events for automations, concurrency, artifacts, work pools/queues by @github-actions[bot] in #22230

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.4…3.7.5

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3.7.4 - From cradle to grave

Released on June 05, 2026 New Features 🎉

• Emit lifecycle events (created, updated, deleted) for all domain objects including variables, flows, block documents, block types, concurrency limits, artifact collections, and automations by @chrisguidry in #22226

Enhancements ➕➕

• Add Redis-backed cleanup queue backend with optimistic transactions and cross-process wakeups by @desertaxle in #22109
• Add cleanup reconciler for worker channel delivery with lease expiry, retry, and dead-letter policies by @desertaxle in #22205
• Add cleanup delivery dispatcher for routing reserved cleanup messages to workers over WebSocket by @desertaxle in #22206
• Add configurable filter params (automations, sort, limit, offset) to read_automations client methods by @devin-ai-integration[bot] in #22191
• Surface sanitized git clone stderr in error messages when no known hint matches by @zzstoatzz in #22196

Bug Fixes 🐞

• Fix deploy init field parsing by @zzstoatzz in #22183
• Fix parse_obj_as() crash with StopIteration on empty dict by @devteamaegis in #22188
• Fix prompt to save new deployments into an existing prefect.yaml by @zzstoatzz in #22195
• Filter stdlib paths from PYTHONPATH to prevent subprocess CLI breakage by @devin-ai-integration[bot] in #22179
• Recover perpetual services after Redis disruption by @devin-ai-integration[bot] in #22213

Documentation 📓

• Document max request size limit for Prefect Cloud API by @devin-ai-integration[bot] in #22186
• Document flow_run_log_summary automation template variable by @mitchnielsen in #22192
• Clarify runtime auto-install gating conditions by @devin-ai-integration[bot] in #22209
• Document deployment schedule clear command by @devin-ai-integration[bot] in #22221
• Use canonical PREFECT_TASKS_* env vars in retries guide by @devin-ai-integration[bot] in #22235

Development & Tidiness 🧹

• Preserve cyclopts modules in reset_sys_modules by @zzstoatzz in #22194
• Increase hold_timeout in test_wait_for_lock to prevent race condition by @devin-ai-integration[bot] in #22202
• Use automatic=True for cleanup reconciler perpetual service by @devin-ai-integration[bot] in #22225
• Scope uv bytecode compilation to image builds by @zzstoatzz in #22227
• Upgrade UI builder stages from bullseye to bookworm by @devin-ai-integration[bot] in #22231

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.3…3.7.4

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3.7.3 - Scheduler go brrrr

Released on June 01, 2026 Automatic dependency installation for pulled-code deployments is now opt-in. In 3.7.2, the runner would automatically prepare project dependencies when a deployment pulled code containing a pyproject.toml. This behavior is now disabled by default. Set PREFECT_RUNNER_AUTO_INSTALL_DEPENDENCIES=true (or runner.auto_install_dependencies = true in your profile) to re-enable it. Enhancements ➕➕

• Expose WebSocket ping interval/timeout settings for uvicorn by @chuqCTC in #22091
• Activate scheduler partial index for faster scheduling queries by @zzstoatzz in #22111
• Lazify prefect.server package exports for faster imports by @devin-ai-integration[bot] in #22122

Bug Fixes 🐞

• Raise pydantic-settings lower bound to >=2.9.1 by @devin-ai-integration[bot] in #22075
• Cap reconnect_delay exponent to prevent OverflowError by @devin-ai-integration[bot] in #22086
• Guard ZeroDivisionError in RetryFailedTasks when retry_jitter_factor is set without retry_delay by @devteamaegis in #22071
• Redact API URL userinfo in client errors by @devin-ai-integration[bot] in #22098
• Execute local deployment paths in place by @devin-ai-integration[bot] in #22100
• Preserve persisted result metadata by @desertaxle in #22110
• Make runner dependency installation opt-in by @desertaxle in #22116
• Preserve TaskRunRecorder upsert order by @desertaxle in #22112
• Lowercase work pool name in block document names for storage configure by @devin-ai-integration[bot] in #22144
• Remove double client injection in _resolve_flow_for_hooks by @devin-ai-integration[bot] in #22176

Integrations & Dependencies 🤝

• Bump starlette to 1.2.0 for CVE-2026-48710 by @zzstoatzz in #22145

Development & Tidiness 🧹

• Add server-side cleanup queue storage for worker communication by @desertaxle in #22041
• Don’t copy file-derived labels from linked issues by @zzstoatzz in #22115
• Support string keys in temporary_settings by @zzstoatzz in #22120
• Clean up WebSocket ping settings surface and tests by @devin-ai-integration[bot] in #22117
• Fix flaky tests on main — regenerate SettingAccessor and widen timing tolerance by @devin-ai-integration[bot] in #22133
• Add timeout and transport retries to hosted_api_client fixture by @devin-ai-integration[bot] in #22130
• Use direct API calls in suspension integration test by @devin-ai-integration[bot] in #22157
• Use direct API calls in suspension integration test by @devin-ai-integration[bot] in #22152
• Pin local worker registry in test_create_with_unsupported_type by @devin-ai-integration[bot] in #22153
• Remove unneeded clear_db markers from isolated test modules by @devin-ai-integration[bot] in #22102
• Update CODEOWNERS to remove obsolete entries by @desertaxle in #22178

Documentation 📓

• Fix work-pool concurrency command examples by @devin-ai-integration[bot] in #22093
• Clarify non-interactive Prefect Cloud login requirements by @devin-ai-integration[bot] in #22095
• Fix multi-worker server docs Redis requirements by @devin-ai-integration[bot] in #22107

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.2…3.7.3

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3.7.2 - Delete after running

Released on May 22, 2026 Enhancements ➕➕

• Add delete flow run automation action by @zzstoatzz in #22018
• Add worker channel handshake and heartbeat by @desertaxle in #22004
• Add work-pool snapshot delivery to worker channel by @desertaxle in #22026
• Index triggers by expect pattern to avoid O(n) scan in find_interested_triggers by @chuqCTC in #21977
• Cache variable reads within a single resolve_variables() call by @devin-ai-integration[bot] in #22060
• Cache block document template resolution by @zzstoatzz in #22065
• Validate PEP 508 dependencies in execute_bundle_in_subprocess by @theluckystrike in #21916

Bug Fixes 🐞

• Remove redundant submitted_ids set in ScheduledRunPoller by @J3r3myPerera in #21982
• Fix Apprise logger level normalization by @hemantmm in #21709
• Handle concurrent work-pool creation in worker REST fallback by @1fanwang in #21919
• Use stdlib importlib.metadata instead of importlib_metadata backport by @devin-ai-integration[bot] in #22012
• Improve missing block reference error messages by @hemantmm in #21945
• Correctly check process liveness before adding to process map by @J3r3myPerera in #22006
• Fix Azure blob result storage to overwrite on rewrite by @wtfashwin in #22035
• Surface actionable error when UI static files fail due to insufficient disk space by @devin-ai-integration[bot] in #22057
• Route lease renewal failure log through run logger by @zzstoatzz in #22053
• Show clean CLI error for malformed TOML settings files by @devin-ai-integration[bot] in #22030
• Make ZipBuilder storage keys truly content-addressed by @devin-ai-integration[bot] in #22008
• Fix default result store existence checks by @desertaxle in #22058
• Fix worker-channel ready frame returning worker_id=None by @devin-ai-integration[bot] in #22067

Development & Tidiness 🧹

• Make test_flow_parameter_caching deterministic by @devin-ai-integration[bot] in #21973
• Widen suspension propagation window in external-suspension integration test by @devin-ai-integration[bot] in #21972
• Fix flaky test_worker integration test with event subscription race by @devin-ai-integration[bot] in #22010
• Make test_read_flow_runs_filters_by_start_time deterministic by @devin-ai-integration[bot] in #22024
• Speed up client test CI shards by @desertaxle in #22003
• Add import-performance guardrails by @devin-ai-integration[bot] in #22002
• Flip clear_db marker from opt-out to opt-in by @desertaxle in #21918
• Measure true cold imports in CodSpeed benchmarks by @devin-ai-integration[bot] in #22019
• Fix low-risk import cycles by @devin-ai-integration[bot] in #22040

Documentation 📓

• Replace stale prefect run CLI example with python by @devin-ai-integration[bot] in #22013
• Fix stale internal links on work-pools concept page by @devin-ai-integration[bot] in #22031
• Fix retired deployment-doc links in create-deployments page by @devin-ai-integration[bot] in #22061
• Update Airflow migration guide to use prefect deploy + prefect.yaml by @devin-ai-integration[bot] in #22059
• Add delete-flow-run automation action to action types table by @github-actions[bot] in #22021

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.1…3.7.2

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3.7.1 - Don’t touch that dial!

Released on May 16, 2026 Enhancements ➕➕

• Add deployment_name logging variable by @devin-ai-integration[bot] in #21804
• Infer logs page size from API response in CLI by @alighazi288 in #21711
• Add default result storage CLI by @zzstoatzz in #21771
• Add Pydantic-aware tojson template filter by @devin-ai-integration[bot] in #21861
• Add worker channel protocol contract by @desertaxle in #21859
• Add worker channel client with REST fallback by @desertaxle in #21885
• Add worker cleanup executor by @desertaxle in #21895
• Add worker work-pool snapshot handling by @desertaxle in #21898
• Add cancelling_timeout_teardown.v1 cleanup handler by @desertaxle in #21911

Bug Fixes 🐞

• Fix flow run logs download from Prefect UI in browser by @baltic-tea in #21718
• Fix flow run suspension at orchestration boundaries by @desertaxle in #21875
• Clear default result storage when deleting block by @zzstoatzz in #21862
• Preserve trailing slash when redirecting to V2 UI by @zzstoatzz in #21912
• Fix concurrency lease renewal starvation with thread-backed renewal by @desertaxle in #21925
• Enforce tz-aware DateTime on Python >= 3.13 by @zzstoatzz in #21952
• Fix subflow duplication when process is re-executed against same flow_run_id by @devin-ai-integration[bot] in #21951
• Reject COMPLETED→COMPLETED transitions that discard result data by @saschwartz in #21956
• Use tz-aware now("UTC") for last_adhoc_pull timestamp in runner by @J3r3myPerera in #21961
• Guard .get() calls on arbitrary State.data in result-data-loss rules by @devin-ai-integration[bot] in #21967

Integrations & Dependencies 🤝

• Bump prefect-github extra floor to >=0.4.2 by @zzstoatzz in #21946

Development & Tidiness 🧹

• Fix flaky test_flow_run_execute_cancellation_runs_nested_subflow_hooks by @devin-ai-integration[bot] in #21866
• Migrate low-risk private modules to _internal (batch 1 of 3) by @devin-ai-integration[bot] in #21879
• Migrate medium-complexity private modules to _internal (batch 2) by @devin-ai-integration[bot] in #21881
• Migrate _result_records.py and utilities/_engine.py to _internal/ (batch 3) by @devin-ai-integration[bot] in #21880
• Label agents-md-update PRs and exclude from changelog by @devin-ai-integration[bot] in #21910
• Fix duplicated “the” in flow_run_slas test comments by @lphuc2250gma in #21943
• Widen timing tolerance in test_renew_concurrency_lease by @devin-ai-integration[bot] in #21965
• Fix flaky test_reschedule_flow_runs timeout under CI load by @devin-ai-integration[bot] in #21966
• Harden AGENTS.md auto-sync reviews by @devin-ai-integration[bot] in #21975

Documentation 📓

• Document default result storage by @zzstoatzz in #21774
• Document published REST OpenAPI schema by @zzstoatzz in #21844
• Mark server-side default result storage as beta by @zzstoatzz in #21877
• Document context propagation for threads in add-logging guide by @jbbqqf in #21883
• Recommend managed automation for zombie detection by @bunchesofdonald in #21894
• Add unlisted infrastructure debugging overview page by @devin-ai-integration[bot] in #21900
• Note metric-trigger Cloud gating and event prefix difference by @zzstoatzz in #21935

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.7.0…3.7.1

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3.7.0 - Our little features are all grown up 🥲

Released on May 06, 2026 New Features 🎉

• Graduate infrastructure decorators to GA by @desertaxle in #21784
• Promote plugin system from experimental to GA by @desertaxle in #21787
• Add isolated workspace resolver for flow run setup by @desertaxle in #21699

Enhancements ➕➕

• Support inline block placeholder substitution by @hemantmm in #21777
• Render Mermaid.js diagrams in Markdown blocks in ui-v2 by @devin-ai-integration[bot] in #21793
• Eliminate O(N²) checksum scan in read_block_schemas by @VittoriaLanzo in #21754
• Add per-browser UI version switcher by @desertaxle in #21706
• Add server default result storage config surface by @zzstoatzz in #21532
• Route server default result storage through runtime resolution by @zzstoatzz in #21759
• Add flow.generate_mermaid_graph() method for dependency-free flow visualization by @znicholasbrown in #21786
• Route flow-run execute through workspace resolver by @desertaxle in #21796
• Add flow engine module entrypoint by @desertaxle in #21799
• Run prepared pyproject workspaces with uv by @desertaxle in #21801
• Warn when nested ThreadPoolTaskRunner submission would deadlock by @devin-ai-integration[bot] in #21800
• Add cycle detection for block_document references by @Lougarou in #21829

Bug Fixes 🐞

• Use now() helper instead of DateTime.now() in deployment CLI by @devin-ai-integration[bot] in #21769
• Fix race condition in GitRepository.pull_code() with file-based locking by @devin-ai-integration[bot] in #21388
• Retry record_bulk_task_run_events on IntegrityError by @devin-ai-integration[bot] in #21813
• Set custom flow run names before Running events by @devin-ai-integration[bot] in #21803
• Prevent deadlock in mark_deployments_ready / mark_deployments_not_ready by @chuqCTC in #21792
• Fix V2 concurrency lease release errors by @devin-ai-integration[bot] in #21797

Development & Tidiness 🧹

• Avoid run_coro_as_sync deadlock in wait futures test by @devin-ai-integration[bot] in #21766
• Widen timing tolerance for test_flow_run_lateness_when_scheduled by @devin-ai-integration[bot] in #21781
• Widen flow timeout in test_timeout_concurrency_slot_released by @devin-ai-integration[bot] in #21788
• Add apt retry config to old-sqlite.Dockerfile by @devin-ai-integration[bot] in #21814
• Use thread-based pytest-timeout for test_timeout_stops_execution_at_next_task_for_sync_flows by @devin-ai-integration[bot] in #21819
• Add zombie flow detection trigger regression test by @devin-ai-integration[bot] in #21802

Full Changelog: https://github.com/PrefectHQ/prefect/compare/3.6.29…3.7.0

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