diff --git a/make.R b/make.R
index 8677269b1c44784ec094421975533d0b8ec36eff..ebb44d33fff85a069f28f07b80c050b57b099010 100644
--- a/make.R
+++ b/make.R
@@ -82,7 +82,22 @@ system("R CMD check ../onlineforecast_1.0.0.tar.gz")
 # https://win-builder.r-project.org/
 
 
-# Run another version of R
+#-----------------
+# WINDOWS:
+# Install rtools
+# Run in R:
+#writeLines('PATH="${RTOOLS40_HOME}\\usr\\bin;${PATH}"', con = "~/.Renviron")
+# Check if rtools are found:
+#Sys.which("make")
+
+# Must have Makevars and Makevars.win
+# Make the two files, find them and copy into "src"
+#library("RcppArmadillo")
+#RcppArmadillo.package.skeleton("tmp-pkg")
+
+
+#-----------------
+# Run another version of R (a linux in podman)
 # see https://hub.docker.com/u/rocker
 
 # Open terminal and "sudo su" (needed for podman to access files)
diff --git a/src/Makevars b/src/Makevars
new file mode 100644
index 0000000000000000000000000000000000000000..d3e3f4143c50ad561945e7c34e6fe45de229b498
--- /dev/null
+++ b/src/Makevars
@@ -0,0 +1,14 @@
+
+## With R 3.1.0 or later, you can uncomment the following line to tell R to 
+## enable compilation with C++11 (where available)
+##
+## Also, OpenMP support in Armadillo prefers C++11 support. However, for wider
+## availability of the package we do not yet enforce this here.  It is however
+## recommended for client packages to set it.
+##
+## And with R 3.4.0, and RcppArmadillo 0.7.960.*, we turn C++11 on as OpenMP
+## support within Armadillo prefers / requires it
+CXX_STD = CXX11
+
+PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS) 
+PKG_LIBS = $(SHLIB_OPENMP_CXXFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)
diff --git a/src/Makevars.win b/src/Makevars.win
new file mode 100644
index 0000000000000000000000000000000000000000..d3e3f4143c50ad561945e7c34e6fe45de229b498
--- /dev/null
+++ b/src/Makevars.win
@@ -0,0 +1,14 @@
+
+## With R 3.1.0 or later, you can uncomment the following line to tell R to 
+## enable compilation with C++11 (where available)
+##
+## Also, OpenMP support in Armadillo prefers C++11 support. However, for wider
+## availability of the package we do not yet enforce this here.  It is however
+## recommended for client packages to set it.
+##
+## And with R 3.4.0, and RcppArmadillo 0.7.960.*, we turn C++11 on as OpenMP
+## support within Armadillo prefers / requires it
+CXX_STD = CXX11
+
+PKG_CXXFLAGS = $(SHLIB_OPENMP_CXXFLAGS) 
+PKG_LIBS = $(SHLIB_OPENMP_CXXFLAGS) $(LAPACK_LIBS) $(BLAS_LIBS) $(FLIBS)