As far as I know jekyll exclude parameter in config is for preventing some files from build folder. I have some custom *.md files that i dont want in output. however when I exclude them, I also see no html file of my pages and posts in output. Very strange for me.
The reason is because you’re using a wildcard to exclude all .md files.
To exclude only some .md files, list them explicitly or use a pattern to identify them properly: