Both myself and @adamstac are seeing this warning message...
— "warning: already initialized constant WFKV_"
I'm not even sure it's Serve related, but neither he nor I can make heads or tails of it, so I figured I'd ask.
This is coming from Rack itself, which Serve uses. I've been seeing the same warning in a rack app and a Sinatra app that I've been working on.
Looks like this was patched 2 days ago: rack/rack#247
I'm gonna close this as it is not a bug with serve itself.