PrefectHQ/prefect 3.9.1

3.9.1 - This hour is a rerun

on GitHub

3.9.1 - This hour is a rerun

Released on October 30, 2026

Enhancements ➕➕

• Add custom state discovery and filters by @desertaxle in #23490
• Add Run action to the React flows list menu and flow page by @devin-ai-integration[bot] in #23354
• Allow sorting task runs by duration by @nolantonio in #23275
• Allow dismissing the V1 UI sidebar shortcut by @zzstoatzz in #23626
• Enforce duration input minimum by @uinstinct in #23122
• Cache get_timezones() by @tylerjthomas9 in #23531
• Share orchestration clients across automation actions by @fatih-acar in #23255
• Restore advisory Cloud API compatibility checks by @desertaxle in #23624
• Show plain IDs instead of UUID(...) reprs in CLI messages by @LuisFigueroaG in #23650
• Align date picker popover to the start instead of center by @uinstinct in #23655

Bug Fixes 🐞

• Prevent state persistence error from failing success flow by @uinstinct in #22745
• Skip unset Pydantic private attributes when rebuilding models in visit_collection by @devin-ai-integration[bot] in #23515
• Retry flows that return a failed state when retries is configured by @devin-ai-integration[bot] in #23535
• Preserve literal markup and emoji aliases in variable CLI JSON output by @devin-ai-integration[bot] in #23530
• Resolve numeric string dict keys in get_from_dict by @devin-ai-integration[bot] in #23454
• Begin SQLite write transaction before reading automation buckets by @devin-ai-integration[bot] in #23471
• Fix forked child processes exiting with code 1 because of QueueService at-exit drain by @devin-ai-integration[bot] in #23464
• Serialize context on every ProcessPoolTaskRunner.submit() by @devin-ai-integration[bot] in #23376
• Schedule astop on SIGTERM instead of dropping the coroutine by @devin-ai-integration[bot] in #23346
• Keep flows search input focused while filtering by @devin-ai-integration[bot] in #23338
• Keep daily IntervalSchedule wall-clock time across DST when start is after the change by @devin-ai-integration[bot] in #23205
• Allow the provisioned ECS execution role to create CloudWatch log groups by @Sagargupta16 in #23557
• Fix GitRepository.pull_code() re-cloning a shallow clone on every new commit by @CassianoE in #23351
• Substitute apply_values placeholders in a single pass by @devin-ai-integration[bot] in #23494
• Percent-encode path values in url_for by @devin-ai-integration[bot] in #23493
• Read automation buckets in a single query to avoid refresh race by @devin-ai-integration[bot] in #23604
• Delete every automation with prefect automation delete --all by @cf3901646 in #23521
• Apply both any_ and not_any_ in flow run state filters by @spicysharkco in #23459
• Fix JSON flow results with data or result keys reading back wrong by @devin-ai-integration[bot] in #23377
• Preserve deployment concurrency lease ID on forced flow run state changes by @darshjoshi in #23304
• Fix filter_files aborting on a directory symlink cycle by @aayushbaluni in #23307
• Preserve cron start bounds in repeated DST hours by @zzstoatzz in #23634
• Recover cron occurrences shifted through DST gaps by @zzstoatzz in #23636
• Exit non-zero from flow-run execute when a crash cannot be reported by @devin-ai-integration[bot] in #23393
• Skip repeated cron occurrences during scheduler refills by @zzstoatzz in #23652
• Stop extra cron runs during DST refills on Python 3.11 and 3.12 by @desertaxle in #23672
• Fall back to placeholder for any jsonable_encoder error in Flow.serialize_parameters by @devin-ai-integration[bot] in #23630
• Fix 500 from flow run list endpoints when a parameter exceeds 64 bits by @DEVJHAWAR11 in #23429
• Reset pause keys when a blocking pause is rescheduled by @devin-ai-integration[bot] in #23399
• Read until final state after terminal event in wait_for_flow_run by @devin-ai-integration[bot] in #23669
• Display zero and false enum selections in the UI by @ashutosh8021 in #23656
• Publish duration lower bounds only where validation enforces them by @gaker in #23507
• Read metric triggers on metrics this version doesn't know by @nathandpeterson in #23513
• Fix duplicate retries label in deployments custom run by @uinstinct in #23343
• Show a not-found error from prefect flow-run inspect for missing runs by @LuisFigueroaG in #23329
• Show a not-found error from prefect deployment run --id for missing deployments by @LuisFigueroaG in #23586
• Show an invalid ID error from prefect deployment run --id for malformed IDs by @LuisFigueroaG in #23621
• Show an invalid slug error from prefect block inspect and block delete for extra slashes by @LuisFigueroaG in #23670
• Read every global concurrency limit in prefect transfer by @spicysharkco in #23456
• Add url property to client-side ReceivedEvent by @ethanstoner in #23181
• Prevent incorrect cached task results by preserving DataFrame column order by @uinstinct in #23303
• Raise ObjectUnsupported from the async create_work_pool when the plan doesn't allow the pool by @LuisFigueroaG in #23610
• Fix task returning another task's cached results by @uinstinct in #23468
• Make date range span relative instead of absolute by @uinstinct in #23086
• Fix returned failed states being cached as successful task results by @uinstinct in #23523
• Fix date changing when clicking pm in date selector by @uinstinct in #23622
• Fix "use default value" doing nothing in parameter inputs by @uinstinct in #23657

Integrations & Dependencies 🤝

• Make the server compatible with SQLAlchemy 2.1 by @devin-ai-integration[bot] in #23201
• Lock current prefect-redis and prefect-kubernetes for the Docker image by @devin-ai-integration[bot] in #23537
• Bump stale integration pins in uv.lock and keep them current on release by @devin-ai-integration[bot] in #23527
• Upgrade cyclopts to 5.3.2 and keep CLI exit codes and command names by @gaker in #23646
• Refresh the Python and UI dependency lockfiles by @gaker in #23666
• Move the remaining Node 20 pins to Node 22 by @znicholasbrown in #23509
• Update Node to the October 2026 security releases by @znicholasbrown in #23508
• Bump vite from 8.2.2 to 8.3.4 in /ui-v2 by @dependabot[bot] in #23488
• Bump opentelemetry-api from 1.44.0 to 1.45.1 by @dependabot[bot] in #23539
• Bump zod from 4.5.4 to 4.6.7 in /ui-v2 by @dependabot[bot] in #23547
• Bump graphql-core from 3.2.7 to 3.2.12 by @dependabot[bot] in #23542
• Bump pillow from 12.3.0 to 13.0.0 by @dependabot[bot] in #23541
• Bump virtualenv from 21.7.13 to 21.14.9 by @dependabot[bot] in #23540
• Bump virtualenv from 21.14.9 to 21.14.13 by @dependabot[bot] in #23584
• Bump storybook from 10.6.0 to 10.6.3 in /ui-v2 by @dependabot[bot] in #23549
• Bump lodash-es and mermaid in /ui-v2 by @dependabot[bot] in #23551
• Bump dompurify from 3.4.16 to 3.4.17 in /ui-v2 by @dependabot[bot] in #23548
• Bump undici from 8.11.2 to 8.12.3 in /ui-v2 by @dependabot[bot] in #23581
• Bump fast-uri from 3.1.7 to 3.1.9 in /ui-v2 by @dependabot[bot] in #23582
• Bump msgpack from 1.2.1 to 1.2.3 by @dependabot[bot] in #23633
• Bump qs from 6.16.0 to 6.17.0 in /ui by @dependabot[bot] in #23632

Development & Tidiness 🧹

• Fix flaky TestRemoteFileSystem tree-project tests by @devin-ai-integration[bot] in #23554
• Fix flaky worker channel tests racing a 1s wall-clock deadline by @devin-ai-integration[bot] in #23450
• Fix flaky TestWorkerLogging test caused by logging leak from prefect config CLI tests by @devin-ai-integration[bot] in #23297
• Fix flaky StateFilter discovery cap search test by @devin-ai-integration[bot] in #23556
• Fix flaky date_diff_seconds from-now tests by @devin-ai-integration[bot] in #23451
• Fix background worker shutdown hang when worker cancellation is lost by @devin-ai-integration[bot] in #23511
• Ignore Python 3.15 multi-threaded fork warning in forked child service test by @devin-ai-integration[bot] in #23562
• Fix flaky events E2E tests by filtering by exact resource IDs by @devin-ai-integration[bot] in #23579
• Fix flaky TestProcessPoolTaskRunner::test_submit_remains_non_blocking by @devin-ai-integration[bot] in #23605
• Fix flaky TestFlowRunLogs tests by filtering logs by flow run by @devin-ai-integration[bot] in #23611
• Refresh and verify Docker image CA trust stores by @zzstoatzz in #23517
• Document SQLite BEGIN IMMEDIATE contract in server AGENTS.md by @devin-ai-integration[bot] in #23560
• Document _pendulum_call contract in src/prefect AGENTS.md by @devin-ai-integration[bot] in #23499

Documentation 📓

• Document Python 3.15 support and ISO duration inputs for within by @devin-ai-integration[bot] in #23498
• Document flow retries for returned Failed states by @devin-ai-integration[bot] in #23543
• Document microbatch task runs and partial success in PrefectDbtRunner by @devin-ai-integration[bot] in #23361
• Correct the reverse-proxy UI settings table by @himanshuchawla0807-gif in #23479
• Document event.url in automation templates by @devin-ai-integration[bot] in #23607
• Set canonical URLs to www.prefect.io by @maximearmstrong in #23641
• Link to the docs at www.prefect.io/docs by @maximearmstrong in #23642
• Fix broken docs links and stop redirecting missing pages to the homepage by @maximearmstrong in #23651

Full Changelog: 3.9.0...3.9.1