diff --git a/CHANGES b/CHANGES
index dc89627..06ee483 100644
--- a/CHANGES
+++ b/CHANGES
@@ -23,8 +23,8 @@ The following are the changes from calc version 2.14.0.15 to date:
 
     Added .PHONY rule, just after all rule, to Makefiles.
 
-    Added ${MSYS} Makefile variable for users under Windows 11 who
-    use MINGW64_NT.
+    Added ${WINGM} Makefile variable for users under Windows 11 who
+    use Cygwin and the MinGW64 packages.
 
     Fixed missing quotes in the PASSDOWN makefile variables.
 
diff --git a/Makefile b/Makefile
index 7f59f49..74c10df 100644
--- a/Makefile
+++ b/Makefile
@@ -77,8 +77,8 @@ endif
 ifeq ($(hardware),)
 hardware=$(shell uname -m 2>/dev/null)
 endif
-ifeq ($(MSYS),)
-MSYS=$(shell uname -o 2>/dev/null)
+ifeq ($(MINGW),)
+MINGW=$(shell uname -o 2>/dev/null)
 endif
 #
 #endif	/* end of skip for non-Gnu makefiles */
@@ -107,8 +107,13 @@ SHELL= /bin/bash
 ifeq ($(target),Darwin)
 SHELL:= /bin/sh
 endif
-ifeq ($(MSYS),Msys)
-SHELL:= "git-bash.exe"
+#
+# If you are using Cygwin with MinGW64 packages
+# then we will also need to use the Cygwin runtime enviroment
+# and the calc Cygwin make target.
+##
+ifeq ($(MINGW),Cygwin)
+target:= Cygwin
 endif
 #
 #endif	/* end of skip for non-Gnu makefiles */
@@ -2202,7 +2207,7 @@ CUSTOM_PASSDOWN=  \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
     MV="${MV}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     PREFIX="${PREFIX}" \
     PURIFY="${PURIFY}" \
     Q="${Q}" \
@@ -2255,7 +2260,7 @@ HELP_PASSDOWN= \
     LIBDIR="${LIBDIR}" \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     MV="${MV}" \
     PREFIX="${PREFIX}" \
     Q="${Q}" \
@@ -2290,7 +2295,7 @@ CAL_PASSDOWN= \
     LIBDIR="${LIBDIR}" \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     MV="${MV}" \
     PREFIX="${PREFIX}" \
     Q="${Q}" \
@@ -2326,7 +2331,7 @@ CSCRIPT_PASSDOWN= \
     LIBDIR="${LIBDIR}" \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     MV="${MV}" \
     PREFIX="${PREFIX}" \
     Q="${Q}" \
@@ -4876,7 +4881,7 @@ env:
 	@echo 'MANMAKE=${MANMAKE}'; echo ''
 	@echo 'MANMODE=${MANMODE}'; echo ''
 	@echo 'MKDIR=${MKDIR}'; echo ''
-	@echo 'MSYS=${MSYS}'; echo ''
+	@echo 'MINGW=${MINGW}'; echo ''
 	@echo 'MV=${MV}'; echo ''
 	@echo 'NROFF=${NROFF}'; echo ''
 	@echo 'NROFF_ARG=${NROFF_ARG}'; echo ''
diff --git a/Makefile.simple b/Makefile.simple
index 2ee96ec..0484b1f 100644
--- a/Makefile.simple
+++ b/Makefile.simple
@@ -1614,7 +1614,7 @@ CUSTOM_PASSDOWN=  \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
     MV="${MV}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     PREFIX="${PREFIX}" \
     PURIFY="${PURIFY}" \
     Q="${Q}" \
@@ -1667,7 +1667,7 @@ HELP_PASSDOWN= \
     LIBDIR="${LIBDIR}" \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     MV="${MV}" \
     PREFIX="${PREFIX}" \
     Q="${Q}" \
@@ -1702,7 +1702,7 @@ CAL_PASSDOWN= \
     LIBDIR="${LIBDIR}" \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     MV="${MV}" \
     PREFIX="${PREFIX}" \
     Q="${Q}" \
@@ -1738,7 +1738,7 @@ CSCRIPT_PASSDOWN= \
     LIBDIR="${LIBDIR}" \
     MAKE_FILE=Makefile \
     MKDIR="${MKDIR}" \
-    MSYS="${MSYS}" \
+    MINGW="${MINGW}" \
     MV="${MV}" \
     PREFIX="${PREFIX}" \
     Q="${Q}" \
@@ -4169,7 +4169,7 @@ env:
 	@echo 'MANMAKE=${MANMAKE}'; echo ''
 	@echo 'MANMODE=${MANMODE}'; echo ''
 	@echo 'MKDIR=${MKDIR}'; echo ''
-	@echo 'MSYS=${MSYS}'; echo ''
+	@echo 'MINGW=${MINGW}'; echo ''
 	@echo 'MV=${MV}'; echo ''
 	@echo 'NROFF=${NROFF}'; echo ''
 	@echo 'NROFF_ARG=${NROFF_ARG}'; echo ''
diff --git a/README.WINDOWS b/README.WINDOWS
index 2dd0607..bd5a825 100644
--- a/README.WINDOWS
+++ b/README.WINDOWS
@@ -27,18 +27,15 @@ NOTE: The main developers do not have access to a Windows based platform.
 
 We were given this advice from a Windows 11 developer:
 
-    Windows 11 users should try:
+    Windows 11 users could use Cygwin:
 
-	https://git-scm.com/downloads
+        https://cygwin.com/install.html
 
-	    When you run the installer wizard, make sure you choose/check
-	    the git bash installer option.
+    and include all MinGW64 packages.
 
-	https://www.mingw-w64.org/
-
-	    Runtime environment for GCC & LLVM for 32 and 64 bit Windows
-
-	    We suggest Windows 11 users consider using MINGW64.
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
+=-= Compiling calc via virtual machine under Windows 11 =-=
+=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 
 We would prefer a Windows 11 solution that does not require a Windows 11
 developer to install a Linux virtual machine.  Nevertheless, a Windows 11