One of the best things he did was to make a single file with a list of all the keywords. In that case he was able to set things up so that if the file was inaccurate the build would fail; not sure if that’s practical for the various feature flags, but it’s helpful to have a single place. Here’s a link to an interesting WebKit mailing list message about one of the steps in that <https://lists.webkit.org/pipermail/webkit-dev/2012-February/019501.html>.

I’d love us to find a similar way to “manage” and make it so someone can look over the entire list of feature flags and conditionals so we can spot problems easily.