Vibe.d & DUB

[Chris]

Based on "examples/http_server" I get the following errors when I 
add an external source file:

source/app.d(26): Error: module app function 
vibe.http.server.handleRequest is private
source/app.d(26): Error: function vibe.http.server.listenHTTP 
(HTTPServerSettings settings, void delegate(HTTPServerRequest 
req, HTTPServerResponse res) request_handler) is not callable 
using argument types (HTTPServerSettings, bool function(Stream 
http_stream, TCPConnection tcp_connection, HTTPServerListener 
listen_info, ref HTTPServerSettings settings, ref bool 
keep_alive))
Error: DMD compile run failed with exit code 1

"sourceFiles": [
     "../../project/module/sourcefile.d"
],

I also link to a library I copied to "source/lib" in the 
server-project folder.

If I exclude the reference from package.config and from app.d it 
works perfectly fine.

If I include the external file and exclude the line 
"listenHTTP(settings, &handleRequest);", it compiles (but of 
course does nothing.

I couldn't find anything on google nor in the documentation about 
vibe.http.server.listenHTTP

Something trivial, I suppose, but I cannot find it.