

I would have assumed the hosts file got cached, indexed and re-read if the file changes. Surely it’s not read and parsed for every single hostname lookup.
My adblock list is in BIND9 anyway, so I don’t get this issue. I can see it definitely takes a second or two to parse the whole list on startup.
The backend and frontend on the product I work on are like this.
As long as you remember that booleans are not strings and should always be parsed if they are, this won’t be a problem.
I am yet to see a boolean.parse() implementation in the wild that is case sensitive.