Cylc 8.0b3 Caveats

This is a beta release of Cylc. There are some loose ends and features which have not yet been (re)implemented.

Cylc Flow

CLI Change

We plan to move to a new way of specifying workflow, cycles, tasks and jobs on the command line (with back support for the old format).

This will allow targetting of multiple workflows with a single command e.g:

$ cylc stop '*'  # stop everything
Trigger Edit

Functionality removed pending reimplementation.


The new “reflow” functionality, which allows multiple (potentially concurrent) executions of the same workflow in a single scheduler, is not fully supported by all commands

Browser Based UI

The old “GUI” has been replaced by the new browser-based “UI”.

Graph View

There is no graph view in the new Cylc UI as yet. A new graph view will be developed providing both “live” (AKA cylc gui) and “offline” (AKA cylc graph) functionalities.

Static Graph Visualization

Not yet reimplemented for Cylc 8. As an interim measure the cylc graph` command can generate a basic PNG image of a workflow graph if Graphviz is installed in the Cylc environment.

Log Files

The ability to view job logs and other files in the web UI is yet to be implemented. For the moment:

  • use cylc cat-log

  • look in your cylc-run directory

  • use Cylc Review from Cylc 7.9.5/7.8.10 (the latest version is compatible with Cylc 8)

Multiple Selection

Multiple selection is yet to be implemented, however, it is possible to issue action for multiple tasks (e.g. kill) without using multiple selection:

  • From the UI click on a workflow/cycle/task/job.

  • Find the action you want to call (e.g. kill).

  • Click the pencil symbol next to this action.

  • Edit the workflows/cycles/tasks/jobs in the form and press submit.


Installing Workflows

At present there is no way to view or install non-installed workflows (a.k.a. source workflows) in the UI.

Rose Edit

Rose Edit is awaiting reimplementation in the UI.

Trigger Edit

Functionality removed pending reimplementation.

Xtrigger Visibility

Xtriggers are not yet visible in the UI.

Documentation / Orientation Guide

Some form of documentation will be provided within the UI itself.

Terminal User Interface

The cylc tui command (Tui) replaces the old cylc monitor. It provides a tree view that is very similar to the Cylc UI and supports some control functionality.


TUI currently refreshes its display every second. Large workflows which change rapidly may evolve faster than TUI is able to keep pace with which will cause TUI to freeze.

A more performant implementation which does not rely on a scheduled global update will follow in due course.


The old cylc gscan GUI has been removed. You can now find the gscan display on the left-hand side of the Cylc UI.

In a future release cylc tui will be able to list workflows in a similar way.

UI Server


A full-featured authorization system has been implemented for Cylc 8, but the UI doesn’t yet provide easy access to other users’ UI Servers.


The ability to route Cylc commands via the UIS is planned for a future relase