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

For more detail see the component changelogs:

Cylc 8.1.0

Cylc Components








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

Graph View

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

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

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.

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.


Combined Commands

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

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 8.0.0

Cylc Components







The first official release of Cylc 8.

For a summary of changes see the migration guide.