Cylc 8.0rc2 Released

We are pleased to announce the second release candidate for Cylc 8.

This release is suitable for early adopters and acceptance testing.


Migration Guide


Please raise questions about migration issues or feedback issues in the Cylc 8 migration category:

Cylc 8 Migration

This category is for the migration from Cylc 7 (and Rose 2019) to Cylc 8.

Future Releases

Cylc 8.0rc2 will be followed by further release candidates where we will attempt to address feedback and fix any issues reported. We will continue to develop new Cylc features after the official 8.0.0 release.

The web-based GUI (cylc-ui) will see a steady trickle of features in the following release candidates and beyond into future Cylc 8 releases. The familiar Cylc 7 “dot” and “graph” views will arrive in a future Cylc 8 release along with static graph visualisation, multi-selection and other improvements.

Beta Users

Workflows run with earlier beta versions before Cylc 8.0rc1 cannot be restarted due to a database change.

The Cylc UI Server configuration file path has changed from ~/.cylc/hub/ to ~/.cylc/uiserver/ The same for the site-config where hub has been replaced by uiserver.


[2022-03-28 17:39] We are currently investigating issues with the cylc-uiserver 1.0.1 package on conda-forge which appears to be lacking some required files. The PyPi package is unaffected.

[2022-03-28 18:40] We have identified the issue, caused by a bug in a tool used in the deployment process. We have released a new build of the cylc-uiserver project (build 2) which fixes the issue, this should become available in the next couple of hours.

[2022-03-29 09:50] The new build is available, Conda should choose it in preference to the older one, if not it can be explicitly specified like so: conda install 'cylc-uiserver=1.0.1=pyhd8ed1ab_2'.