XCode unable to compile Poco project, undefined symbols

I've been looking for a proper HTTP parser in C++ and today I found that Poco has support for both parsing HTTP requests, setting up a server and also setting up a HTTPS server along with other cool features and I'm eager to start using it.

I've got a problem with compiling a small example though, the project is setup as a stdc++11 project, I've set the header and library search path to /usr/local/include and /usr/local/lib and have linked the libraries themselves in the Other Linker Flags in this order "-lPocoNet -lPocoUtil -lPocoFoundation -lPocoXML -lPocoJSON" the order of which doesn't seem to matter.

The code itself doesn't throw any errors within XCode, it's just when I try to compile it I get these reference errors, I've fixed 38 others of them by adding the libraries to the Other Linker Flags option but these two errors won't go away.

The error I'm getting is the following

Ld /Users/zezioen/Library/Developer/Xcode/DerivedData/NitroServer-gpnzdaqmezqcauegsmrabobsxotk/Build/Products/Debug/NitroServer normal x86_64
cd /Users/zezioen/stack/Projecten/CPP/NitroServer
export MACOSX_DEPLOYMENT_TARGET=10.11
/Applications/http://ift.tt/17KlLIW -arch x86_64 -isysroot /Applications/http://ift.tt/1jCtz97 -L/Users/zezioen/Library/Developer/Xcode/DerivedData/NitroServer-gpnzdaqmezqcauegsmrabobsxotk/Build/Products/Debug -L/Users/zezioen/stack/Projecten/CPP/NitroServer/lib -L/usr/local/lib -F/Users/zezioen/Library/Developer/Xcode/DerivedData/NitroServer-gpnzdaqmezqcauegsmrabobsxotk/Build/Products/Debug -F/Users/zezioen/stack/Projecten/CPP/NitroServer/lib -filelist /Users/zezioen/Library/Developer/Xcode/DerivedData/NitroServer-gpnzdaqmezqcauegsmrabobsxotk/Build/Intermediates/NitroServer.build/Debug/NitroServer.build/Objects-normal/x86_64/NitroServer.LinkFileList -mmacosx-version-min=10.11 -Xlinker -no_deduplicate -lPocoNet -lPocoUtil -lPocoFoundation -lPocoXML -lPocoJSON -stdlib=libstdc++ -Xlinker -dependency_info -Xlinker /Users/zezioen/Library/Developer/Xcode/DerivedData/NitroServer-gpnzdaqmezqcauegsmrabobsxotk/Build/Intermediates/NitroServer.build/Debug/NitroServer.build/Objects-normal/x86_64/NitroServer_dependency_info.dat -o /Users/zezioen/Library/Developer/Xcode/DerivedData/NitroServer-gpnzdaqmezqcauegsmrabobsxotk/Build/Products/Debug/NitroServer

Undefined symbols for architecture x86_64:
  "Poco::Net::HTTPMessage::setContentType(std::string const&)", referenced from:
      MyRequestHandler::handleRequest(Poco::Net::HTTPServerRequest&, Poco::Net::HTTPServerResponse&) in main.o
  "Poco::Util::Application::handleOption(std::string const&, std::string const&)", referenced from:
      vtable for MyServerApp in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

What do I have to do in order to get the project to build?