diff -ur gpgmepp.org/lang/cpp/src/callbacks.cpp gpgmepp/lang/cpp/src/callbacks.cpp
--- gpgmepp.org/lang/cpp/src/callbacks.cpp	2016-10-18 19:22:02.000000000 +0200
+++ gpgmepp/lang/cpp/src/callbacks.cpp	2017-11-20 18:03:04.290060900 +0100
@@ -40,7 +40,9 @@
 #include <cassert>
 #include <cerrno>
 #include <cstring>
+#if HAVE_UNISTD_H
 #include <unistd.h>
+#endif
 #include <stdlib.h>
 
 static inline gpgme_error_t make_err_from_syserror()
diff -ur gpgmepp.org/lang/cpp/src/data.h gpgmepp/lang/cpp/src/data.h
--- gpgmepp.org/lang/cpp/src/data.h	2017-03-24 15:20:32.000000000 +0100
+++ gpgmepp/lang/cpp/src/data.h	2017-11-20 17:23:24.802711200 +0100
@@ -31,6 +31,11 @@
 #include <algorithm>
 #include <memory>
 
+#ifdef _MSC_VER
+#  include <BaseTsd.h>
+typedef SSIZE_T ssize_t;
+#endif
+
 namespace GpgME
 {
 
diff -ur gpgmepp.org/lang/cpp/src/editinteractor.cpp gpgmepp/lang/cpp/src/editinteractor.cpp
--- gpgmepp.org/lang/cpp/src/editinteractor.cpp	2017-03-09 09:01:10.000000000 +0100
+++ gpgmepp/lang/cpp/src/editinteractor.cpp	2017-11-20 18:09:33.022674700 +0100
@@ -33,9 +33,11 @@
 
 #include <gpgme.h>
 
-#ifdef _WIN32
+#ifdef _MSC_VER
 # include <io.h>
-#include <windows.h>
+# include <windows.h>
+# include <BaseTsd.h>
+  typedef SSIZE_T ssize_t;
 #else
 # include <unistd.h>
 #endif
diff -ur gpgmepp.org/lang/cpp/src/gpgmepp_export.h gpgmepp/lang/cpp/src/gpgmepp_export.h
--- gpgmepp.org/lang/cpp/src/gpgmepp_export.h	2016-08-04 15:03:09.000000000 +0200
+++ gpgmepp/lang/cpp/src/gpgmepp_export.h	2017-11-20 16:57:47.805691100 +0100
@@ -30,14 +30,14 @@
 #  ifndef GPGMEPP_EXPORT
 #    ifdef BUILDING_GPGMEPP
         /* We are building this library */
-#      ifdef WIN32
+#      ifdef _MSC_VER
 #       define GPGMEPP_EXPORT __declspec(dllexport)
 #      else
 #       define GPGMEPP_EXPORT __attribute__((visibility("default")))
 #      endif
 #    else
         /* We are using this library */
-#      ifdef WIN32
+#      ifdef _MSC_VER
 #       define GPGMEPP_EXPORT __declspec(dllimport)
 #      else
 #       define GPGMEPP_EXPORT __attribute__((visibility("default")))
@@ -46,7 +46,7 @@
 #  endif
 
 #  ifndef GPGMEPP_NO_EXPORT
-#    ifdef WIN32
+#    ifdef _MSC_VER
 #     define GPGMEPP_NO_EXPORT
 #    else
 #     define GPGMEPP_NO_EXPORT __attribute__((visibility("hidden")))
@@ -55,7 +55,11 @@
 #endif
 
 #ifndef GPGMEPP_DEPRECATED
-#  define GPGMEPP_DEPRECATED __attribute__ ((__deprecated__))
+#  ifdef _MSC_VER
+#    define GPGMEPP_DEPRECATED __declspec(deprecated("deprecated"))
+#  else
+#    define GPGMEPP_DEPRECATED __attribute__ ((__deprecated__))
+#  endif
 #endif
 
 #ifndef GPGMEPP_DEPRECATED_EXPORT
diff -ur gpgmepp.org/lang/cpp/src/interfaces/dataprovider.h gpgmepp/lang/cpp/src/interfaces/dataprovider.h
--- gpgmepp.org/lang/cpp/src/interfaces/dataprovider.h	2016-05-17 14:32:37.000000000 +0200
+++ gpgmepp/lang/cpp/src/interfaces/dataprovider.h	2017-11-20 18:03:11.332715700 +0100
@@ -31,6 +31,11 @@
 
 #include <gpg-error.h>
 
+#ifdef _MSC_VER
+#  include <BaseTsd.h>
+typedef SSIZE_T ssize_t;
+#endif
+
 namespace GpgME
 {
 
diff -ur gpgmepp.org/lang/cpp/src/key.cpp gpgmepp/lang/cpp/src/key.cpp
--- gpgmepp.org/lang/cpp/src/key.cpp	2017-03-20 20:10:15.000000000 +0100
+++ gpgmepp/lang/cpp/src/key.cpp	2017-11-20 17:44:50.321858800 +0100
@@ -34,11 +34,17 @@
 #include <gpgme.h>
 
 #include <string.h>
+#if HAVE_STRINGS_H
 #include <strings.h>
+#endif
 #include <cassert>
 #include <istream>
 #include <iterator>
 
+#ifdef _MSC_VER
+#  define strcasecmp _stricmp
+#endif
+
 const GpgME::Key::Null GpgME::Key::null;
 
 namespace GpgME
diff -ur gpgmepp.org/lang/qt/src/qgpgme_export.h gpgmepp/lang/qt/src/qgpgme_export.h
--- gpgmepp.org/lang/qt/src/qgpgme_export.h	2016-11-03 17:32:30.000000000 +0100
+++ gpgmepp/lang/qt/src/qgpgme_export.h	2017-11-20 16:58:27.395388000 +0100
@@ -40,14 +40,14 @@
 #  ifndef QGPGME_EXPORT
 #    ifdef BUILDING_QGPGME
         /* We are building this library */
-#      ifdef WIN32
+#      ifdef _WIN32
 #       define QGPGME_EXPORT __declspec(dllexport)
 #      else
 #       define QGPGME_EXPORT __attribute__((visibility("default")))
 #      endif
 #    else
         /* We are using this library */
-#      ifdef WIN32
+#      ifdef _WIN32
 #       define QGPGME_EXPORT __declspec(dllimport)
 #      else
 #       define QGPGME_EXPORT __attribute__((visibility("default")))
@@ -56,7 +56,7 @@
 #  endif
 
 #  ifndef QGPGME_NO_EXPORT
-#    ifdef WIN32
+#    ifdef _WIN32
 #     define QGPGME_NO_EXPORT
 #    else
 #     define QGPGME_NO_EXPORT __attribute__((visibility("hidden")))
@@ -65,7 +65,11 @@
 #endif
 
 #ifndef QGPGME_DEPRECATED
-#  define QGPGME_DEPRECATED __attribute__ ((__deprecated__))
+#  ifdef _MSC_VER
+#    define QGPGME_DEPRECATED __declspec(deprecated("deprecated"))
+#  else
+#    define QGPGME_DEPRECATED __attribute__ ((__deprecated__))
+#  endif
 #endif
 
 #ifndef QGPGME_DEPRECATED_EXPORT