Last I migrated from WordPress to Jekyll, and I have a vague memory that it was painful. Now after many years, I had to do another migration/upgrade because the template I built on seems to have been abandoned by the author.
The migration process was OK ish, but like any migration there were issues.
The vanilla Jekyll looks pretty boring (bad) and misses many features. I ended up picking up a theme that looks pretty awesome and well maintained (at least for now). The theme is named as Chirpy and can be found on GitHub. If you like it, send the folk a coffee.
I learned that Jekyll sucks when coming to tag and category. Well it is very simple to tag and categorize a post, but one has to manually create a page for each tag/category in order to be able to see all the posts belonging to the tag/category. On one hand I can understand the rational, while on the other hand, a built-in implementation (1, 2) would be very well appreciate. Yes there are plugins supporting this to some extent but none of them is supported by GitHub pages. The result? Everyone is customizing a GitHub building/publishing workflow, including Chirpy, more concretely, which is done by this script. The problem of the script is plain string processing instead of proper YAML parsing, and that resulted missing many tags and categories in my case, unfortunately. And because of this, I had to disable the Test Site step in GitHub workflow.