diff --git a/src/gui/CMakeLists.txt b/src/gui/CMakeLists.txt
index 428bde8c..3f250fc0 100644
--- a/src/gui/CMakeLists.txt
+++ b/src/gui/CMakeLists.txt
@@ -6,17 +6,25 @@ set (CMAKE_AUTORCC ON)
 set (CMAKE_AUTOUIC ON)
 set (CMAKE_INCLUDE_CURRENT_DIR ON)
 
-file (GLOB GUI_SOURCE_FILES src/*.cpp src/*.h)
-file (GLOB GUI_UI_FILES src/*.ui)
-
 if (WIN32)
-    set (GUI_RC_FILES res/win/Barrier.rc)
+    set (resources res/win/Barrier.rc)
+    set (arch "win32")
+else()
+    set (arch "unix")
+endif()
+
+file (GLOB sources src/*.cpp src/${arch}/*.cpp)
+file (GLOB headers src/*.h src/${arch}/*.h)
+file (GLOB designs src/*.ui)
+
+if (BARRIER_ADD_HEADERS)
+    list (APPEND sources ${headers})
 endif()
 
 add_executable (barrier WIN32
-    ${GUI_SOURCE_FILES}
-    ${GUI_UI_FILES}
-    ${GUI_RC_FILES}
+    ${sources}
+    ${designs}
+    ${resources}
     res/Barrier.qrc
 )
 
@@ -32,7 +40,7 @@ if (WIN32)
                   HINTS ENV BONJOUR_SDK_HOME
                   PATH_SUFFIXES "Lib/x64")
     set_target_properties (barrier PROPERTIES LINK_FLAGS "/NODEFAULTLIB:LIBCMT")
-    target_link_libraries (barrier ${DNSSD_LIB})
+    target_link_libraries (barrier ${DNSSD_LIB} Ws2_32.lib Iphlpapi.lib)
 elseif (APPLE)
     find_library(APPSERVICES_LIB ApplicationServices)
     target_link_libraries(barrier ${APPSERVICES_LIB})
diff --git a/src/gui/src/DefaultInterfaceIP.h b/src/gui/src/DefaultInterfaceIP.h
new file mode 100644
index 00000000..a3c14571
--- /dev/null
+++ b/src/gui/src/DefaultInterfaceIP.h
@@ -0,0 +1,10 @@
+#pragma once
+
+#include <string>
+
+namespace Debauchee
+{
+
+std::string default_interface_ip();
+
+}
diff --git a/src/gui/src/ZeroconfService.cpp b/src/gui/src/ZeroconfService.cpp
index 02902ee5..66706253 100644
--- a/src/gui/src/ZeroconfService.cpp
+++ b/src/gui/src/ZeroconfService.cpp
@@ -20,6 +20,7 @@
 #include "MainWindow.h"
 #include "ZeroconfRegister.h"
 #include "ZeroconfBrowser.h"
+#include "DefaultInterfaceIP.h"
 
 #include <QtNetwork>
 #include <QMessageBox>
@@ -34,12 +35,6 @@
 #include <stdlib.h>
 #endif
 
-static const QStringList preferedIPAddress(
-                QStringList() <<
-                "192.168." <<
-                "10." <<
-                "172.");
-
 const char* ZeroconfService:: m_ServerServiceName = "_barrierServerZeroconf._tcp";
 const char* ZeroconfService:: m_ClientServiceName = "_barrierClientZeroconf._tcp";
 
@@ -124,27 +119,6 @@ void ZeroconfService::errorHandle(DNSServiceErrorType errorCode)
         tr("Error code: %1.").arg(errorCode));
 }
 
-QString ZeroconfService::getLocalIPAddresses()
-{
-    QStringList addresses;
-    foreach (const QHostAddress& address, QNetworkInterface::allAddresses()) {
-        if (address.protocol() == QAbstractSocket::IPv4Protocol &&
-            address != QHostAddress(QHostAddress::LocalHost)) {
-            addresses.append(address.toString());
-        }
-    }
-
-    foreach (const QString& preferedIP, preferedIPAddress) {
-        foreach (const QString& address, addresses) {
-            if (address.startsWith(preferedIP)) {
-                return address;
-            }
-        }
-    }
-
-    return "";
-}
-
 bool ZeroconfService::registerService(bool server)
 {
     bool result = true;
@@ -159,7 +133,7 @@ bool ZeroconfService::registerService(bool server)
         else {
             m_pZeroconfRegister = new ZeroconfRegister(this);
             if (server) {
-                QString localIP = getLocalIPAddresses();
+                QString localIP = QString::fromStdString(Debauchee::default_interface_ip());
                 if (localIP.isEmpty()) {
                     QMessageBox::warning(m_pMainWindow, tr("Barrier"),
                         tr("Failed to get local IP address. "
diff --git a/src/gui/src/ZeroconfService.h b/src/gui/src/ZeroconfService.h
index 929cd055..8a3b8beb 100644
--- a/src/gui/src/ZeroconfService.h
+++ b/src/gui/src/ZeroconfService.h
@@ -42,7 +42,6 @@ private slots:
     void errorHandle(DNSServiceErrorType errorCode);
 
 private:
-    QString getLocalIPAddresses();
     bool registerService(bool server);
 
 private:
diff --git a/src/gui/src/main.cpp b/src/gui/src/main.cpp
index 73251d52..b42f90ce 100644
--- a/src/gui/src/main.cpp
+++ b/src/gui/src/main.cpp
@@ -67,6 +67,13 @@ int main(int argc, char* argv[])
     /* Workaround for QTBUG-40332 - "High ping when QNetworkAccessManager is instantiated" */
     ::setenv ("QT_BEARER_POLL_TIMEOUT", "-1", 1);
 #endif
+
+#if _WIN32
+    // winsock needs to be initialized for DefaultInterfaceIP
+    WSADATA wd;
+    WSAStartup(MAKEWORD(2, 0), &wd);
+#endif
+
 	QCoreApplication::setOrganizationName("Debauchee");
 	QCoreApplication::setOrganizationDomain("github.com");
 	QCoreApplication::setApplicationName("Barrier");
diff --git a/src/gui/src/unix/DefaultInterfaceIP.cpp b/src/gui/src/unix/DefaultInterfaceIP.cpp
new file mode 100644
index 00000000..ed82e327
--- /dev/null
+++ b/src/gui/src/unix/DefaultInterfaceIP.cpp
@@ -0,0 +1,79 @@
+#include "IfAddrsResource.h"
+#include "SocketResource.h"
+#include <sys/ioctl.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#ifdef __linux__
+#include <linux/wireless.h>
+#else
+#include <net/if.h>
+#include <net/if_media.h>
+#endif
+
+#include <string>
+#include <cstring>
+
+namespace Debauchee
+{
+
+static bool is_wireless(const char * ifname, const SocketResource& sock)
+{
+#ifdef __linux__
+    struct iwreq req;
+    ::memset(&req, 0, sizeof(struct iwreq));
+    ::strncpy(req.ifr_name, ifname, IFNAMSIZ - 1);
+    return ioctl(sock, SIOCGIWMODE, &req) >= 0;
+#else
+    struct ifmediareq req;
+    ::memset(&req, 0, sizeof(struct ifmediareq));
+    ::strncpy(req.ifm_name, ifname, IFNAMSIZ - 1);
+    if (ioctl(sock, SIOCGIFMEDIA, &req) >= 0 &&
+        (req.ifm_status & IFM_AVALID)
+    ) {
+        return IFM_TYPE(req.ifm_active) == IFM_IEEE80211;
+    }
+    return false;
+#endif
+}
+
+static bool is_wireless(const char * ifname)
+{
+    if (ifname) {
+        SocketResource sock(AF_INET, SOCK_DGRAM, 0);
+        if (sock.is_valid()) {
+            return is_wireless(ifname, sock);
+        }
+    }
+    return false;
+}
+
+std::string default_interface_ip()
+{
+    std::string wirelessAddress;
+    IfAddrsResource ifa;
+    if (ifa.is_valid()) {
+        for (struct ifaddrs * next = ifa; next; next = next->ifa_next) {
+            auto sain = (struct sockaddr_in *)next->ifa_addr;
+            if (!sain || sain->sin_family != AF_INET ||
+                !(next->ifa_flags & IFF_RUNNING) ||
+                (next->ifa_flags & IFF_LOOPBACK)
+               ) {
+                continue;
+            }
+            std::string address = inet_ntoa(sain->sin_addr);
+            // take first wired address right away
+            if (!is_wireless(next->ifa_name)) {
+                return address;
+            }
+            // save first wireless address to be used if we don't find a wired one
+            if (wirelessAddress.empty()) {
+                wirelessAddress = address;
+            }
+        }
+    }
+    return wirelessAddress;
+}
+
+}
+
diff --git a/src/gui/src/unix/IfAddrsResource.h b/src/gui/src/unix/IfAddrsResource.h
new file mode 100644
index 00000000..57c1a2ba
--- /dev/null
+++ b/src/gui/src/unix/IfAddrsResource.h
@@ -0,0 +1,32 @@
+#include <sys/types.h>
+#include <ifaddrs.h>
+
+namespace Debauchee
+{
+
+class IfAddrsResource
+{
+public:
+    explicit IfAddrsResource() :
+        _valid(getifaddrs(&_ifa) == 0)
+    {
+    }
+
+    ~IfAddrsResource()
+    {
+        if (_valid) {
+            freeifaddrs(_ifa);
+        }
+    }
+
+    bool is_valid() const { return _valid; }
+
+    operator struct ifaddrs * () const { return _ifa; }
+
+private:
+    bool _valid;
+    struct ifaddrs * _ifa;
+};
+
+}
+
diff --git a/src/gui/src/unix/SocketResource.h b/src/gui/src/unix/SocketResource.h
new file mode 100644
index 00000000..57eb1727
--- /dev/null
+++ b/src/gui/src/unix/SocketResource.h
@@ -0,0 +1,32 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+namespace Debauchee
+{
+
+class SocketResource
+{
+public:
+    explicit SocketResource(int domain, int type, int protocol) :
+        _fd(socket(domain, type, protocol))
+    {
+    }
+
+    ~SocketResource()
+    {
+        if (is_valid()) {
+            close(_fd);
+        }
+    }
+
+    bool is_valid() const { return _fd >= 0; }
+
+    operator int() const { return _fd; }
+
+private:
+    int _fd;
+};
+
+}
+
diff --git a/src/gui/src/win32/DefaultInterfaceIP.cpp b/src/gui/src/win32/DefaultInterfaceIP.cpp
new file mode 100644
index 00000000..81796953
--- /dev/null
+++ b/src/gui/src/win32/DefaultInterfaceIP.cpp
@@ -0,0 +1,100 @@
+// REQUIRES: Ws2_32.lib, Iphlpapi.lib
+// REQUIRES: WSAStartup(..)
+
+// see comments regarding WSAAddressToStringA in address_string(..)
+#define _WINSOCK_DEPRECATED_NO_WARNINGS
+
+#include <WinSock2.h>
+#include <iphlpapi.h>
+#include <string>
+#include "HeapResource.h"
+
+namespace Debauchee
+{
+
+static ULONG get_addresses(IP_ADAPTER_ADDRESSES * addresses, PULONG sz)
+{
+    return GetAdaptersAddresses(AF_INET,
+        GAA_FLAG_SKIP_ANYCAST | GAA_FLAG_SKIP_MULTICAST | GAA_FLAG_SKIP_DNS_SERVER | GAA_FLAG_SKIP_FRIENDLY_NAME,
+        NULL, addresses, sz);
+}
+
+static std::string address_string(const SOCKET_ADDRESS& address)
+{
+    // planning to use this with Qt but QString does not have a c'tor
+    // for wide strings so we need to force the ANSI API here
+    DWORD szStrAddress = 1023;
+    char strAddress[1024];
+    if (WSAAddressToStringA(address.lpSockaddr, address.iSockaddrLength, NULL, strAddress, &szStrAddress)) {
+        return "";
+    }
+    return strAddress;
+}
+
+static std::string first_unicast_address(IP_ADAPTER_UNICAST_ADDRESS * unicast)
+{
+    while (unicast) {
+        auto address = address_string(unicast->Address);
+        if (!address.empty()) {
+            return address;
+        }
+        unicast = unicast->Next;
+    }
+    return std::string();
+}
+
+static bool is_useable_interface(const IP_ADAPTER_ADDRESSES * ifa)
+{
+    return
+        // is an ethernet or wireless interface AND
+        (ifa->IfType == IF_TYPE_ETHERNET_CSMACD || ifa->IfType == IF_TYPE_IEEE80211) &&
+        // is up
+        ifa->OperStatus == IfOperStatusUp;
+}
+
+static std::string default_ip_address(const IP_ADAPTER_ADDRESSES * next)
+{
+    std::string wirelessAddress;
+    for ( ; next; next = next->Next) {
+        if (!is_useable_interface(next)) {
+            continue;
+        }
+        std::string address = first_unicast_address(next->FirstUnicastAddress);
+        if (address.empty()) {
+            continue;
+        }
+        // take first wired address right away
+        if (next->IfType == IF_TYPE_ETHERNET_CSMACD) {
+            return address;
+        }
+        // save first wireless address to be used if we don't find a wired one
+        if (wirelessAddress.empty()) {
+            wirelessAddress = address;
+        }
+    }
+    return wirelessAddress;
+}
+
+std::string default_interface_ip()
+{
+    const ULONG DefaultSzAddresses = 15 * 1024; // 15k recommended by msdn
+    ULONG szAddresses = DefaultSzAddresses;
+    HeapResource<IP_ADAPTER_ADDRESSES> addresses(GetProcessHeap(), 0, DefaultSzAddresses);
+    if (addresses.is_valid()) {
+        ULONG result;
+        while (ERROR_BUFFER_OVERFLOW == (result = get_addresses(addresses, &szAddresses))) {
+            // add more space in case more adapters have shown up
+            szAddresses += DefaultSzAddresses;
+            swap(addresses, HeapResource<IP_ADAPTER_ADDRESSES>(GetProcessHeap(), 0, szAddresses));
+            if (!addresses.is_valid()) {
+                break;
+            }
+        }
+        if (result == ERROR_SUCCESS) {
+            return default_ip_address(addresses);
+        }
+    }
+    return std::string();
+}
+
+}
diff --git a/src/gui/src/win32/HeapResource.h b/src/gui/src/win32/HeapResource.h
new file mode 100644
index 00000000..aedce90e
--- /dev/null
+++ b/src/gui/src/win32/HeapResource.h
@@ -0,0 +1,48 @@
+#pragma once
+
+namespace Debauchee
+{
+
+template<class T>
+class HeapResource
+{
+public:
+    explicit HeapResource(HANDLE heap, DWORD flags, SIZE_T sz) :
+        _heap(heap),
+        _flags(flags),
+        _mem((T*)HeapAlloc(heap, flags, sz))
+    {
+    }
+
+    HeapResource(HeapResource<T>&& other)
+        : _mem(NULL)
+    {
+        swap(*this, other);
+    }
+
+    ~HeapResource()
+    {
+        if (is_valid()) {
+            HeapFree(_heap, _flags, _mem);
+        }
+    }
+
+    friend void swap(HeapResource<T>& first, HeapResource<T>& second)
+    {
+        using std::swap;
+        swap(first._heap, second._heap);
+        swap(first._flags, second._flags);
+        swap(first._mem, second._mem);
+    }
+
+    bool is_valid() const { return _mem != NULL; }
+
+    operator T*() const { return _mem; }
+
+private:
+    HANDLE _heap;
+    DWORD _flags;
+    T * _mem;
+};
+
+}