diff --git a/CMakeLists.txt b/CMakeLists.txt
index cbdd35d..ca306ea 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -43,7 +43,7 @@ if(NOT CMAKE_BUILD_TYPE)
   set(CMAKE_BUILD_TYPE Release)
 endif()
 
-set(SILENCE "-Wno-unused-parameter -Wno-unused-variable -Wno-missing-field-initializers") 
+set(SILENCE "-Wno-unused-parameter -Wno-unused-variable -Wno-missing-field-initializers")
 
 # Release - Optimization and no debug info
 # Debug - No optimization, debug info
@@ -55,20 +55,20 @@ set(LIBZT_FLAGS_DEBUG "-DZT_SDK=1 -DLIBZT_TRACE=1 -DLWIP_DEBUG=1 -DLIBZT_DEBUG=1
 
 if(WIN32)
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc -DNOMINMAX")	
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /EHsc -DNOMINMAX")
 else()
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fstack-protector")
 	set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG}")
 	set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -fstack-protector")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${LIBZT_FLAGS} -O3 -Wall -Wextra -std=c++11")
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${LIBZT_FLAGS} ${SILENCE} -O3 -Wall -Wextra -std=c++11")
 	set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} ${LIBZT_FLAGS_DEBUG} ${SILENCE} -std=c++11 -DLWIP_DEBUG=1")
-	set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} ${LIBZT_FLAGS} -O3 -std=c++11")
+	set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} ${LIBZT_FLAGS} ${SILENCE} -O3 -std=c++11")
 	set(LWIP_PORT_DIR ${PROJ_DIR}/ext/lwip-contrib/ports/unix/port)
 endif()
 
 # --- PLATFORM-SPECIFIC CONFIG
 
-# ANDROID-specific 
+# ANDROID-specific
 if(${CMAKE_SYSTEM_NAME} MATCHES "Android")
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -DSOCKLEN_T_DEFINED=1")
 	include_directories (/Users/joseph/Library/Android/sdk/ndk-bundle/sysroot/usr/include/arm-linux-androideabi)
@@ -108,9 +108,42 @@ endif()
 add_definitions(-DSDK_JNI=1)
 endif()
 
-# --- BUILD TARGETS
+# --- BUILD TARGETS (FINAL PRODUCT)
 
-# lwip 
+# libzt (static)
+set(LIBZT_SRC_DIR ${PROJ_DIR}/src)
+include_directories ("${LIBZT_SRC_DIR}")
+include_directories ("${PROJ_DIR}/include")
+file (GLOB libzt_src_glob ${LIBZT_SRC_DIR}/*.cpp)
+add_library (zt STATIC
+	$<TARGET_OBJECTS:lwip_obj>
+	$<TARGET_OBJECTS:zto_obj>
+	$<TARGET_OBJECTS:http_obj> ${libzt_src_glob})
+if(WIN32)
+	target_link_libraries (zt ws2_32)
+	target_link_libraries (zt ${lshlwapi_LIBRARY_PATH})
+	target_link_libraries (zt ${liphlpapi_LIBRARY_PATH})
+else()
+	target_link_libraries (zt pthread)
+endif()
+set_target_properties (zt PROPERTIES OUTPUT_NAME zt)
+
+# libzt (shared)
+add_library (ztshared SHARED
+	$<TARGET_OBJECTS:lwip_pic_obj>
+	$<TARGET_OBJECTS:zto_pic_obj>
+	$<TARGET_OBJECTS:http_pic_obj> ${libzt_src_glob})
+set_target_properties (ztshared PROPERTIES OUTPUT_NAME zt)
+
+if(${CMAKE_SYSTEM_NAME} MATCHES "Android")
+	target_link_libraries (zt lwip zto android log)
+else()
+	target_link_libraries (zt pthread)
+endif()
+
+# --- OBJECT LIBRARIES (INTERMEDIATE)
+
+# lwip_obj
 set(LWIP_SRC_DIR ${PROJ_DIR}/ext/lwip/src)
 include_directories (${LWIP_SRC_DIR}/include)
 include_directories (${LWIP_PORT_DIR}/include)
@@ -121,11 +154,12 @@ file (GLOB lwip_src_glob
 	${LWIP_SRC_DIR}/core/*.c 
 	${LWIP_SRC_DIR}/core/ipv4/*.c 
 	${LWIP_SRC_DIR}/core/ipv6/*.c)
-add_library (lwip STATIC ${lwip_src_glob})
-add_library (lwip_pic STATIC ${lwip_src_glob})
-set_target_properties (lwip_pic PROPERTIES POSITION_INDEPENDENT_CODE ON)
+list(REMOVE_ITEM lwip_src_glob ${LWIP_SRC_DIR}/netif/slipif.c)
+add_library (lwip_obj OBJECT ${lwip_src_glob})
+add_library (lwip_pic_obj OBJECT ${lwip_src_glob})
+set_target_properties (lwip_pic_obj PROPERTIES POSITION_INDEPENDENT_CODE ON)
 
-# zto 
+# zto_obj
 set(ZTO_SRC_DIR ${PROJ_DIR}/ext/ZeroTierOne)
 include_directories (${ZTO_SRC_DIR}/include)
 include_directories (${ZTO_SRC_DIR}/osdep)
@@ -137,47 +171,20 @@ file (GLOB zto_src_glob
 	${ZTO_SRC_DIR}/osdep/OSUtils.cpp
 	${ZTO_SRC_DIR}/controller/*.cpp
 	${ZTO_SRC_DIR}/osdep/ManagedRoute.cpp)
-add_library (zto STATIC ${zto_src_glob})
-target_link_libraries (zto http)
-target_link_libraries (zto zt)
+add_library (zto_obj OBJECT ${zto_src_glob})
 if(WIN32)
 	target_link_libraries (zto ws2_32)
 	target_link_libraries (zto ${lshlwapi_LIBRARY_PATH})
 	target_link_libraries (zto ${liphlpapi_LIBRARY_PATH})
 endif()
-add_library (zto_pic STATIC ${zto_src_glob})
-target_link_libraries (zto_pic http_pic zt)
-set_target_properties (zto_pic PROPERTIES POSITION_INDEPENDENT_CODE ON)
+add_library (zto_pic_obj OBJECT ${zto_src_glob})
+set_target_properties (zto_pic_obj PROPERTIES POSITION_INDEPENDENT_CODE ON)
 
-# http 
+# http_obj
 # HTTP Control Plane for ZT Service
-add_library (http STATIC "${ZTO_SRC_DIR}/ext/http-parser/http_parser.c")
-add_library (http_pic STATIC "${ZTO_SRC_DIR}/ext/http-parser/http_parser.c")
-set_target_properties (http_pic PROPERTIES POSITION_INDEPENDENT_CODE ON)
-
-# libzt (static)
-set(LIBZT_SRC_DIR ${PROJ_DIR}/src)
-include_directories ("${LIBZT_SRC_DIR}")
-include_directories ("${PROJ_DIR}/include")
-file (GLOB libzt_src_glob ${LIBZT_SRC_DIR}/*.cpp)
-add_library (zt ${libzt_src_glob})
-if(WIN32)
-	target_link_libraries (zto ws2_32)
-	target_link_libraries (zto ${lshlwapi_LIBRARY_PATH})
-	target_link_libraries (zto ${liphlpapi_LIBRARY_PATH})
-endif()
-set_target_properties (zt PROPERTIES OUTPUT_NAME zt)
-target_link_libraries (zt zto lwip)
-
-# libzt (shared)
-add_library (ztshared SHARED ${libzt_src_glob})
-target_link_libraries (ztshared zto_pic lwip_pic)
-set_target_properties (ztshared PROPERTIES OUTPUT_NAME zt)
-if(${CMAKE_SYSTEM_NAME} MATCHES "Android")
-	target_link_libraries (zt lwip zto android log)
-else()
-	target_link_libraries (zt pthread lwip zto)
-endif()
+add_library (http_obj OBJECT "${ZTO_SRC_DIR}/ext/http-parser/http_parser.c")
+add_library (http_pic_obj OBJECT "${ZTO_SRC_DIR}/ext/http-parser/http_parser.c")
+set_target_properties (http_pic_obj PROPERTIES POSITION_INDEPENDENT_CODE ON)
 
 # --- TEST APPLICATIONS AND EXAMPLES
 
@@ -194,23 +201,23 @@ if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Android")
 	    get_filename_component (testname ${testname} NAME)
 	    add_executable (${testname} ${testsourcefile})
 	if(WIN32)
-	    target_link_libraries (${testname} lwip zto zt)
+	    target_link_libraries (${testname} zt)
 	else()
 		target_link_libraries (${testname} zt pthread dl)
 	endif()
 	endforeach (testsourcefile ${APP_SOURCES})
 
+if(NOT WIN32)
 	# selftest
 	add_executable (selftest ${PROJ_DIR}/test/selftest.cpp)
 	target_compile_options (selftest PRIVATE -D__SELFTEST__)
 	if(WIN32)
-		target_link_libraries (selftest lwip zto zt ${ws2_32_LIBRARY_PATH} ${lshlwapi_LIBRARY_PATH} ${liphlpapi_LIBRARY_PATH})
+		target_link_libraries (selftest zt ${ws2_32_LIBRARY_PATH} ${lshlwapi_LIBRARY_PATH} ${liphlpapi_LIBRARY_PATH})
 	else()
-		target_link_libraries (selftest pthread lwip zto zt)
+		target_link_libraries (selftest zt pthread)
 	endif()
-
 	# nativetest
 	add_executable (nativetest ${PROJ_DIR}/test/selftest.cpp)
 	target_compile_options (nativetest PRIVATE -D__NATIVETEST__)
-	target_link_libraries (nativetest lwip zto zt)
 endif()
+endif()
\ No newline at end of file
diff --git a/examples/cpp/ipv4simple/ipv4server_udp.cpp b/examples/cpp/ipv4simple/ipv4server_udp.cpp
index a7b5309..755d969 100644
--- a/examples/cpp/ipv4simple/ipv4server_udp.cpp
+++ b/examples/cpp/ipv4simple/ipv4server_udp.cpp
@@ -51,7 +51,7 @@ int main(int argc, char **argv)
 	std::string path      = argv[1];
 	std::string nwidstr   = argv[2];
 	int bind_port         = atoi(argv[3]);
-	int w=0, r=0, err=0, sockfd, accfd, flags = 0;
+	int w=0, r=0, err=0, sockfd = 0, accfd = 0, flags = 0;
 	char rbuf[32];
 	memset(rbuf, 0, sizeof rbuf);
 
diff --git a/ext/lwip.patch b/ext/lwip.patch
index 04482fd..0a651b3 100644
--- a/ext/lwip.patch
+++ b/ext/lwip.patch
@@ -1,13 +1,30 @@
 diff --git a/src/api/sockets.c b/src/api/sockets.c
-index b7632489..f6ab59f6 100644
+index b7632489..786a294e 100644
 --- a/src/api/sockets.c
 +++ b/src/api/sockets.c
 @@ -44,6 +44,8 @@
   *
   */
  
-+#include <errno.h>
++//#include <errno.h>
 +
  #include "lwip/opt.h"
  
  #if LWIP_SOCKET /* don't build if not configured for use in lwipopts.h */
+diff --git a/src/include/lwip/errno.h b/src/include/lwip/errno.h
+index 641cffb0..cec43f7f 100644
+--- a/src/include/lwip/errno.h
++++ b/src/include/lwip/errno.h
+@@ -174,7 +174,11 @@ extern "C" {
+ #define  EMEDIUMTYPE    124  /* Wrong medium type */
+ 
+ #ifndef errno
+-extern int errno;
++#if defined(__linux__) && !defined(__ANDROID__)
++	#include <errno.h>
++#else
++	extern int errno;
++#endif
+ #endif
+ 
+ #else /* LWIP_PROVIDE_ERRNO */
diff --git a/include/VirtualTap.h b/include/VirtualTap.h
index 5e212fc..fde8020 100644
--- a/include/VirtualTap.h
+++ b/include/VirtualTap.h
@@ -30,11 +30,12 @@
  * Virtual Ethernet tap device
  */
 
-#ifndef ZT_VIRTUALTAP_HPP
-#define ZT_VIRTUALTAP_HPP
+#ifndef ZT_VIRTUALTAP_H
+#define ZT_VIRTUALTAP_H
 
+#ifndef _MSC_VER
 extern int errno;
-
+#endif
 
 #include "Mutex.hpp"
 #include "MulticastGroup.hpp"
diff --git a/include/lwipopts.h b/include/lwipopts.h
index 9c3f9ee..fadd433 100644
--- a/include/lwipopts.h
+++ b/include/lwipopts.h
@@ -39,16 +39,14 @@
 #ifndef __LWIPOPTS_H__
 #define __LWIPOPTS_H__
 
-//#define LWIP_SUPPORT_CUSTOM_PBUF 	0
-
 /*
  *  Provides its own errno
  */
 
 #if __ANDROID__
 #define LWIP_PROVIDE_ERRNO          0
-#else
-#define LWIP_PROVIDE_ERRNO          0
+#elif !defined(_MSC_VER)
+#define LWIP_PROVIDE_ERRNO          1
 #endif
 
 /*
diff --git a/src/ZT1Service.cpp b/src/ZT1Service.cpp
index f903717..b85541d 100644
--- a/src/ZT1Service.cpp
+++ b/src/ZT1Service.cpp
@@ -93,7 +93,7 @@ VirtualTap *getTapByAddr(ZeroTier::InetAddress *addr)
 	for (size_t i=0; i<vtaps.size(); i++) {
 		s = (VirtualTap*)vtaps[i];
 		// check address schemes
-		for (ssize_t j=0; j<s->_ips.size(); j++) {
+		for (int j=0; j<(int)(s->_ips.size()); j++) {
 			if ((s->_ips[j].isV4() && addr->isV4()) || (s->_ips[j].isV6() && addr->isV6())) {
 				/* DEBUG_EXTRA("looking at tap %s, <addr=%s> --- for <%s>", s->_dev.c_str(),
 				s->_ips[j].toString(ipbuf), addr->toIpString(ipbuf2)); */
@@ -283,7 +283,7 @@ int zts_get_address_at_index(
 		return err;
 	}
 	_vtaps_lock.lock();
-	if (index > -1 && index <= tap->_ips.size()) {
+	if (index > -1 && index <= (int)tap->_ips.size()) {
 		memcpy(addr, &(tap->_ips[index]), *addrlen);
 		*addrlen = tap->_ips[index].isV4() ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6);
 		err = 0;
diff --git a/src/libzt.cpp b/src/libzt.cpp
index 38ec851..40a13a4 100644
--- a/src/libzt.cpp
+++ b/src/libzt.cpp
@@ -420,7 +420,7 @@ int platform_adjusted_socket_family(int family)
 	 if (family == 2) {
 		 return AF_INET;
 	 }
-	 family; // 10
+	 return -1;
 #endif
 }
 
diff --git a/test/selftest.cpp b/test/selftest.cpp
index 9e1af51..731814c 100644
--- a/test/selftest.cpp
+++ b/test/selftest.cpp
@@ -551,7 +551,7 @@ void tcp_select_server(TCP_UNIT_TEST_SIG_4)
 #else
 					r = _READ(fd_i, rbuf, len);
 #endif
-					if (r == msg.length()) {
+					if (r == (int)msg.length()) {
 						rx_num++;
 						DEBUG_TEST("rx=%d", rx_num);
 					}
@@ -563,7 +563,7 @@ void tcp_select_server(TCP_UNIT_TEST_SIG_4)
 #else
 					w = _WRITE(fd_i, msg.c_str(), len);
 #endif
-					if (w == msg.length()) {
+					if (w == (int)msg.length()) {
 						tx_num++;
 						DEBUG_TEST("tx=%d", tx_num);
 					}
@@ -638,7 +638,7 @@ void tcp_select_client(TCP_UNIT_TEST_SIG_4)
 #else
 					r = _READ(fd_i, rbuf, len);
 #endif
-					if (r == msg.length()) {
+					if (r == (int)msg.length()) {
 						rx_num++;
 						DEBUG_TEST("rx=%d", rx_num);
 					}
@@ -650,7 +650,7 @@ void tcp_select_client(TCP_UNIT_TEST_SIG_4)
 #else
 					w = _WRITE(fd_i, msg.c_str(), len);
 #endif
-					if (w == msg.length()) {
+					if (w == (int)msg.length()) {
 						tx_num++;
 						DEBUG_TEST("tx=%d", tx_num);
 					}
@@ -962,7 +962,7 @@ void udp_client_4(UDP_UNIT_TEST_SIG_4)
 		int serverlen = sizeof(struct sockaddr_storage);
 		// rx
 		r = _RECVFROM(fd, rbuf, STR_SIZE, 0, (struct sockaddr *)&saddr, (socklen_t *)&serverlen);
-		if (r == strlen(msg.c_str())) {
+		if (r == (int)strlen(msg.c_str())) {
 			sleep(ARTIFICIAL_SOCKET_LINGER);
 			err = _CLOSE(fd);
 			DEBUG_TEST("%s, err=%d, r=%d, w=%d", testname.c_str(), err, r, w);