diff --git a/kde/applications/cantor/cantor-19.12.1-Windows.diff b/kde/applications/cantor/cantor-19.12.1-Windows.diff
new file mode 100644
index 00000000..2d6a2e88
--- /dev/null
+++ b/kde/applications/cantor/cantor-19.12.1-Windows.diff
@@ -0,0 +1,27 @@
+diff -ruNa cantor-19.12.1.orig/src/backends/R/rserver/rserver.cpp cantor-19.12.1/src/backends/R/rserver/rserver.cpp
+--- cantor-19.12.1.orig/src/backends/R/rserver/rserver.cpp	2020-01-06 14:49:54.000000000 +0100
++++ cantor-19.12.1/src/backends/R/rserver/rserver.cpp	2020-02-02 10:40:27.197011563 +0100
+@@ -33,7 +33,11 @@
+ #include <QDebug>
+ #include <KLocalizedString>
+ 
++#ifdef Q_OS_WIN
++#include <process.h>
++#else
+ #include <unistd.h>
++#endif
+ 
+ //R includes
+ #include <R.h>
+diff -ruNa cantor-19.12.1.orig/src/backends/R/rsession.cpp cantor-19.12.1/src/backends/R/rsession.cpp
+--- cantor-19.12.1.orig/src/backends/R/rsession.cpp	2020-01-06 14:49:54.000000000 +0100
++++ cantor-19.12.1/src/backends/R/rsession.cpp	2020-02-02 10:39:21.189441040 +0100
+@@ -62,7 +62,7 @@
+     m_process->waitForReadyRead();
+     qDebug()<<m_process->readAllStandardOutput();
+ 
+-    m_rServer = new org::kde::Cantor::R(QString::fromLatin1("org.kde.Cantor.R-%1").arg(m_process->pid()),  QLatin1String("/"), QDBusConnection::sessionBus(), this);
++    m_rServer = new org::kde::Cantor::R(QString::fromLatin1("org.kde.Cantor.R-%1").arg(m_process->processId()),  QLatin1String("/"), QDBusConnection::sessionBus(), this);
+ 
+     connect(m_rServer, &org::kde::Cantor::R::statusChanged, this, &RSession::serverChangedStatus);
+     connect(m_rServer,  &org::kde::Cantor::R::expressionFinished, this, &RSession::expressionFinished);
diff --git a/kde/applications/cantor/cantor.py b/kde/applications/cantor/cantor.py
index 07b1193f..0bf571f5 100644
--- a/kde/applications/cantor/cantor.py
+++ b/kde/applications/cantor/cantor.py
@@ -1,55 +1,57 @@
 import info
 
 
 class subinfo(info.infoclass):
     def setTargets(self):
         self.versionInfo.setDefaultValues()
         for ver in ["19.12.0", "19.12.1"]:
             self.patchToApply[ver] = [('cantor-19.12.0-MSVC-libmarkdown.diff', 1)]
+        for ver in ["19.12.1"]:
+            self.patchToApply[ver] = [('cantor-19.12.1-Windows.diff', 1)]
 
         self.description = "Cantor"
 
     def setDependencies(self):
         self.runtimeDependencies["virtual/base"] = None
         self.buildDependencies["kde/frameworks/extra-cmake-modules"] = None
         self.buildDependencies["dev-utils/png2ico"] = None
         #self.runtimeDependencies["dev-utils/python3"] = None
         self.runtimeDependencies["libs/qt5/qtbase"] = None
         self.runtimeDependencies["qt-libs/poppler"] = None
         # R backend fails compiling with MSVC
         if not CraftCore.compiler.isMSVC():
             self.runtimeDependencies["binary/r-base"] = None
         #self.runtimeDependencies["binary/python-libs"] = None
         self.runtimeDependencies["kde/frameworks/tier1/kconfig"] = None
         self.runtimeDependencies["kde/frameworks/tier2/kcrash"] = None
         self.runtimeDependencies["kde/frameworks/tier2/kdoctools"] = None
         self.runtimeDependencies["kde/frameworks/tier3/knewstuff"] = None
         self.runtimeDependencies["kde/frameworks/tier3/kiconthemes"] = None
         self.runtimeDependencies["kde/frameworks/tier3/ktexteditor"] = None
         self.runtimeDependencies["kde/frameworks/tier1/kcoreaddons"] = None
         self.runtimeDependencies["kde/frameworks/tier1/karchive"] = None
         self.runtimeDependencies["kde/frameworks/tier3/kparts"] = None
         self.runtimeDependencies["kde/frameworks/tier2/kpty"] = None
         self.runtimeDependencies["kde/frameworks/tier3/ktextwidgets"] = None
         self.runtimeDependencies["kde/frameworks/tier3/kio"] = None
         self.runtimeDependencies["kde/frameworks/tier1/ki18n"] = None
         self.runtimeDependencies["kde/frameworks/tier3/kxmlgui"] = None
         self.runtimeDependencies["kde/applications/analitza"] = None
 
 
 from Package.CMakePackageBase import *
 
 
 class Package(CMakePackageBase):
     def __init__(self):
         CMakePackageBase.__init__(self)
         if CraftCore.compiler.isMSVC():
             self.subinfo.options.make.supportsMultijob = False
 
         if OsUtils.isWin():
             self.r_dir = os.path.join(CraftCore.standardDirs.craftRoot(), "lib", "R", "bin", "x64")
             self.subinfo.options.configure.args = "-DR_EXECUTABLE=" + OsUtils.toUnixPath(os.path.join(self.r_dir, "R.exe"))
             self.subinfo.options.configure.args += " -DR_R_LIBRARY=" + OsUtils.toUnixPath(os.path.join(self.r_dir, "R.dll"))
 
         pythonPath = CraftCore.settings.get("Paths", "PYTHON")
         self.subinfo.options.configure.args += f" -DPYTHONLIBS3_LIBRARY={pythonPath}"