I keep two TiddlyWiki [0] files, one public, one private.
If I feel that a certain note can become its own piece of knowledge in a Zettlekasten fashion and can have any value for someone else, I put it in my public file and I run a script that will copy it to my hosting provider. My public site is a single file! [1].
Me too, I find Tiddlywiki perfect for this kind of use! You may have seen it, but it is recently made a php script that let you save directly to your server and create a public version where private tiddlers are removed or censored [0]. That way you only need to manage a single file. But it sounds as you have found a good way of doing it already:)
If I feel that a certain note can become its own piece of knowledge in a Zettlekasten fashion and can have any value for someone else, I put it in my public file and I run a script that will copy it to my hosting provider. My public site is a single file! [1].
[0] https://tiddlywiki.com/
[1] https://ramirosalas.com/