diff --git a/net/except.cpp b/net/except.cpp
index 398389d2..86851d02 100644
--- a/net/except.cpp
+++ b/net/except.cpp
@@ -20,6 +20,7 @@
 #include "except.hpp"
 
 #include "../debug.hpp"
+#include "../types/casts.hpp"
 
 
 //-----------------------------------------------------------------------------
@@ -38,11 +39,15 @@ net::error::error (int _code):
 { CHECK (_code != 0); }
 
 
+//-----------------------------------------------------------------------------
 std::string
 net::error::code_to_string (int code) {
 #ifdef __WIN32
     char message[256];
-    int output = FormatMessage (0, NULL, code, 0, message, sizeof (message), NULL);
+
+    // It should be fine to signcast the code here as Windows guarantees all
+    // error messages are positive but appears to use int for compatibility
+    DWORD output = FormatMessage (0, NULL, sign_cast<unsigned> (code), 0, message, sizeof (message), NULL);
     CHECK_HARD (output != 0);
 
     return std::string (message);
@@ -52,6 +57,7 @@ net::error::code_to_string (int code) {
 }
 
 
+//-----------------------------------------------------------------------------
 void
 net::error::throw_code (int code) {
 #ifdef __WIN32
@@ -78,6 +84,12 @@ net::error::throw_code (int code) {
 }
 
 
+void
+net::error::throw_code (void)
+    { throw_code (last_code ()); }
+
+
+//-----------------------------------------------------------------------------
 void
 net::error::try_code (int err) {
     if (err == 0)
@@ -92,11 +104,7 @@ net::error::try_code (void)
     { try_code (last_code ()); }
 
 
-void
-net::error::throw_code (void)
-    { throw_code (last_code ()); }
-
-
+//-----------------------------------------------------------------------------
 int
 net::error::last_code (void) {
 #ifdef __WIN32
@@ -107,6 +115,7 @@ net::error::last_code (void) {
 }
 
 
+//-----------------------------------------------------------------------------
 template <int CODE>
 net::error_code<CODE>::error_code (void):
     net::error (CODE)
diff --git a/net/socket.cpp b/net/socket.cpp
index f9982f7b..139c5574 100644
--- a/net/socket.cpp
+++ b/net/socket.cpp
@@ -25,8 +25,10 @@
 #include "../log.hpp"
 #include "except.hpp"
 
-#if !defined(HAVE_WINSOCK2_H)
-	#include <sys/socket.h>
+#if defined(HAVE_WINSOCK2_H)
+    #include <winsock2.h>
+#else
+    #include <sys/socket.h>
 #endif
 
 #include <sys/types.h>
@@ -211,8 +213,8 @@ net::socket<D, type::STREAM>::listen (const address_type &_addr, unsigned int _b
 template <domain D>
 typename net::socket<D, type::STREAM>::socket_ptr
 net::socket<D, type::STREAM>::accept (void) {
-    int newfd = ::accept (this->m_fd, NULL, 0);
-    if (newfd < 0)
+    socket_t newfd = ::accept (this->m_fd, NULL, 0);
+    if (newfd == INVALID_SOCKET)
         net::error::throw_code ();
 
     return socket_ptr(new socket<D, type::STREAM> (newfd));
diff --git a/net/types.hpp b/net/types.hpp
index 30b61eee..f2c0bf17 100644
--- a/net/types.hpp
+++ b/net/types.hpp
@@ -41,6 +41,7 @@ namespace net {
     typedef SOCKET socket_t;
 #else
     typedef int socket_t;
+    const socket_t INVALID_SOCKET = -1;
 #endif
 
     /// Defines the protocol family, or communication domain of a socket (see `man socket').
diff --git a/string.cpp b/string.cpp
index b5354f09..0c69d203 100644
--- a/string.cpp
+++ b/string.cpp
@@ -21,6 +21,8 @@
 
 #include <cstring>
 
+#include "types/casts.hpp"
+
 // TODO: Horribly inefficient, but God help you if you're relying on this
 // being efficient in the first place.
 bool
@@ -32,23 +34,24 @@ strbegins (const char *restrict str,
 
 
 #if !defined(HAVE_STRNDUP)
+#include <cstdlib>
+
 // Written by Niels Möller <nisse@lysator.liu.se>
 // Placed in the public domain
 
-char *restrict
+char *
 strndup (const char *restrict s, size_t size)
 {
-    char *r;
-    char *end = (char *)memchr(s, 0, size);
+    char *end = static_cast<char *> (memchr (s, 0, size));
 
     if (end)
         // Length + 1
-        size = end - s + 1;
+        size = sign_cast<size_t> (end - s) + 1u;
 
-    char * r = malloc(size);
+    char * r = static_cast<char *> (malloc (size));
 
     if (size) {
-        memcpy(r, s, size-1);
+        memcpy (r, s, size-1);
         r[size-1] = '\0';
     }
     return r;
diff --git a/string.hpp b/string.hpp
index a885925d..530ee222 100644
--- a/string.hpp
+++ b/string.hpp
@@ -26,8 +26,12 @@ strbegins(const char *restrict str,
 
 
 #if !defined(HAVE_STRNDUP)
-char *restrict
-strndup (const char *restrict s, size_t size);
+#include <cstddef>
+
+extern "C" {
+    char *
+    strndup (const char *restrict s, size_t size);
+}
 #endif
 
 #endif // __UTIL_STRING_HPP