Ask HN: Trying to find back a tool to generate sentences based on rules

There’s a tool I recall seeing on HN a few months back, and I haven’t been able to find it in my bookmarks or by googling the keywords I remember. I’m looking for it now because I’d like to experiment with it, so I’m wondering if any of you remember what it was.

From what I can recall, this tool allows you to generate sentences by giving it rules (probably called a grammar?) on words to choose and how to pair them. It’d pick these randomly and build the final sentence. I remember one of the fancy words being used in there was “production”, but I can’t be sure.

The way I found out about it was through an article written by the person who built the tool. The article explained the basics of how to program the tool and gave examples of the results. Maybe I’m wrong but I recall there being a lot of blue on the page. I also recall that the person sounded Italian, going by their name and some of the words used in the examples. Maybe the name was Luca?

I also recall that this tool was described as the “opposite” of regular expressions, in the sense that the rules you provide it with are used to generate rather than match.

Does anyone else remember this?