It should say a paragraph about what "Lucid" is in this context (or link to such). I have no idea and googling it doesn't seem to help.

Here are a bunch of resources I found on the author's blog (originally posted at https://news.ycombinator.com/item?id=31559388 ):

A book on the language can be found here:

https://billwadge.com/lucid-language/

There are a number of posts on the blog that discuss the background:

https://billwadge.com/2011/03/23/lucid-the-origins/

https://billwadge.com/2011/04/09/lucid-the-temporal-language...

https://billwadge.com/2011/04/27/lucid-the-dataflow-language...

https://billwadge.com/2012/03/31/lucid-eduction/

https://billwadge.com/2019/12/04/pylucid-a-lucid-interpreter...

https://billwadge.com/2019/12/04/implementing-pylucid/

https://billwadge.com/2020/08/11/lucid-the-origin-story/

https://billwadge.com/2021/02/21/intensional-logic-in-contex...

https://billwadge.com/2022/01/22/pylucid-calculating-dimensi...