This page contains a summary of significant changes across all Cylc components for each release.

For more detail see the component changelogs:

Cylc 8.2

Cylc Components







UI now remembers workspace tab layout

New in version cylc-uiserver: 1.4.4

The UI now remembers the layout of your workspace tabs when you navigate away from that workflow. Note that this only applies per browser session.


Upgrade To The Latest Jupyter Releases

New in version cylc-uiserver: 1.4.0

The Cylc UI Server has been updated to work with the latest releases of Jupyter Server and Jupyter Hub.

If you are utilising Cylc’s multi-user functionality then your configuration will require some changes to work with these releases.

See Authorizing Others to Access Your Workflows for more details

Configure The Default View

New in version cylc-uiserver: 1.3.0

You can now configure the view which is opened by default when you navigate to a new workflow in the GUI. Navigate to the settings page to select your chosen view.


In the future we plan to support configuring a layout of multiple views and configuring certain options on those views.


New in version cylc-flow: 8.2.0

When workflows are reloaded, (e.g. by cylc reload), Cylc will now pause the workflow and wait for any preparing tasks to be submitted before proceeding with the reload. Once the reload has been completed, the workflow will be resumed.

You can now see more information about the status of the reload in the workflow status message which appears at the top of the GUI and Tui interfaces.

Cylc 8.1

Cylc Components








Workflows started with Cylc 8.0 which contain multiple flows cannot be restarted with Cylc 8.1 due to database changes.

Analysis View

New in version cylc-uiserver: 1.2.2

The web UI also has a new view for displaying task queue & run time statistics.


Graph View

New in version cylc-uiserver: 1.2.0

The web UI now has a graph view which displays a visualisation of a workflow’s graph:


Family & cycle grouping as well as the ability to view graphs for stopped workflows will be added in later releases.

Log View

New in version cylc-uiserver: 1.2.0

The web UI now has a log view which displays workflow and job log files:


Support for viewing more log files, syntax highlighting, searching and line numbers are planned for future releases.

Edit Runtime

New in version cylc-uiserver: 1.2.0

The web UI now has a command for editing the [runtime] section of a task or family.


Any changes made are broadcast to the running workflow.

Combined Commands

New in version cylc-flow: 8.1.0

Two new commands have been added as short-cuts for common working patterns:

cylc vip

Validate, install and plays a workflow, equivalent to:

cylc validate <path>
cylc install <path>
cylc play <id>
cylc vr

Validate and reinstall a workflow, then either: - reload the workflow if it is running. - restart the workflow if it is stopped.


For more information see the command line help:

cylc vip --help
cylc vr --help

Bash Completion

New in version cylc-flow: 8.1.0

Cylc now provides a high performance Bash completion script which saves you typing:

  • Cylc commands & options

  • Workflow IDs

  • Cycle points

  • Task names

  • Job numbers


Installation instructions.

Cylc 8.0

Cylc Components







The first official release of Cylc 8.

For a summary of changes see the migration guide.