diff --git a/DESCRIPTION b/DESCRIPTION
index 28daedf..5234bf0 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: V8
 Type: Package
 Title: Embedded JavaScript and WebAssembly Engine for R
-Version: 4.2.2.9000
+Version: 4.3.0
 Authors@R: c(
     person("Jeroen", "Ooms", role = c("aut", "cre"), email = "jeroen@berkeley.edu",
       comment = c(ORCID = "0000-0002-4035-0289")),
@@ -32,3 +32,4 @@ RoxygenNote: 7.2.3
 Roxygen: list(load = "installed", markdown = TRUE)
 Language: en-US
 Encoding: UTF-8
+Biarch: true
diff --git a/NEWS b/NEWS
index 39a54c9..78c587c 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,6 @@
 4.3.0
+ - MacOS: update libv8 to 11.2
+ - Windows: use libv8 version 9.1 on all R >= 4.0, drop support for Win2008/Vista
  - Add feature test for V8_ENABLE_SANDBOX, required by some V8 10.8+ (#144)
  - Unbundle 3rd party JS libs that are only needed for examples.
 
diff --git a/configure.win b/configure.win
old mode 100644
new mode 100755
index e69de29..054a64b
--- a/configure.win
+++ b/configure.win
@@ -0,0 +1,6 @@
+#!/bin/sh
+
+# Temp fixups R-3.6 or CRAN legacy Vista server
+if [ "${R_VERSION:0:1}" = "3" ] || [ "$LOCAL_SOFT" = "d:/Compiler/gcc-4.9.3/local330" ]; then
+cp -f tools/legacy.win src/Makevars.win
+fi
diff --git a/src/Makevars.ucrt b/src/Makevars.ucrt
deleted file mode 100644
index 8e79677..0000000
--- a/src/Makevars.ucrt
+++ /dev/null
@@ -1,17 +0,0 @@
-CXX_STD = CXX17
-RWINLIB =../windows/ucrt64
-PKG_CPPFLAGS = -I$(RWINLIB)/include -DV8_COMPRESS_POINTERS
-PKG_LIBS = \
-	-L$(RWINLIB)/lib \
-	-lv8_monolith \
-	-lws2_32 -lwinmm -ldbghelp -lshlwapi -lssp -lz
-
-all: clean winlibs
-
-clean:
-	rm -f $(SHLIB) $(OBJECTS)
-
-winlibs:
-	"${R_HOME}/bin${R_ARCH_BIN}/Rscript.exe" "../tools/ucrtlibs.R"
-
-.PHONY: all winlibs clean
diff --git a/src/Makevars.win b/src/Makevars.win
index 608c72e..26e1ee8 100644
--- a/src/Makevars.win
+++ b/src/Makevars.win
@@ -1,13 +1,10 @@
-VERSION = 6.2.414.50-vista
-CXX_STD = CXX11
-RWINLIB =../windows/libv8-$(VERSION)
-PKG_CPPFLAGS = -I$(RWINLIB)/include -DV8_ENABLE_CHECKS
+CXX_STD = CXX17
+RWINLIB =../windows/mingw$(WIN)
+PKG_CPPFLAGS = -I$(RWINLIB)/include $(subst $(WIN),,-DV8_COMPRESS_POINTERS64)
 PKG_LIBS = \
-	-L$(RWINLIB)/lib${subst gcc ,-,${R_COMPILED_BY}}${R_ARCH} \
-	-L$(RWINLIB)/lib${R_ARCH} \
-	-lv8_base -lv8_libplatform  -lv8_nosnapshot \
-	-lv8_libbase -lv8_libsampler -lv8_builtins_setup -lv8_builtins_generators \
-	-lws2_32 -lwinmm -ldbghelp -lshlwapi
+	-L$(RWINLIB)/lib \
+	-lv8_monolith \
+	-lws2_32 -lwinmm -ldbghelp -lshlwapi -lssp -lz
 
 all: clean winlibs
 
@@ -15,6 +12,6 @@ clean:
 	rm -f $(SHLIB) $(OBJECTS)
 
 winlibs:
-	"${R_HOME}/bin${R_ARCH_BIN}/Rscript.exe" "../tools/winlibs.R" $(VERSION)
+	"${R_HOME}/bin${R_ARCH_BIN}/Rscript.exe" "../tools/winlibs.R"
 
 .PHONY: all winlibs clean
diff --git a/tools/legacy.win b/tools/legacy.win
new file mode 100644
index 0000000..514c9f4
--- /dev/null
+++ b/tools/legacy.win
@@ -0,0 +1,20 @@
+VERSION = 6.2.414.50-vista
+CXX_STD = CXX11
+RWINLIB =../windows/libv8-$(VERSION)
+PKG_CPPFLAGS = -I$(RWINLIB)/include -DV8_ENABLE_CHECKS
+PKG_LIBS = \
+	-L$(RWINLIB)/lib${subst gcc ,-,${R_COMPILED_BY}}${R_ARCH} \
+	-L$(RWINLIB)/lib${R_ARCH} \
+	-lv8_base -lv8_libplatform  -lv8_nosnapshot \
+	-lv8_libbase -lv8_libsampler -lv8_builtins_setup -lv8_builtins_generators \
+	-lws2_32 -lwinmm -ldbghelp -lshlwapi
+
+all: clean winlibs
+
+clean:
+	rm -f $(SHLIB) $(OBJECTS)
+
+winlibs:
+	"${R_HOME}/bin${R_ARCH_BIN}/Rscript.exe" "../tools/oldlibs.R" $(VERSION)
+
+.PHONY: all winlibs clean
diff --git a/tools/oldlibs.R b/tools/oldlibs.R
new file mode 100644
index 0000000..b95831e
--- /dev/null
+++ b/tools/oldlibs.R
@@ -0,0 +1,13 @@
+# Build against mingw-w64 build of libv8
+VERSION <- commandArgs(TRUE)
+LIBDIR <- paste0("../windows/libv8-", VERSION)
+if(!file.exists(paste0(LIBDIR, "/include/v8.h"))){
+  if(getRversion() < "3.3.0") stop("This library requires R 3.3 or newer")
+  download.file(sprintf("https://github.com/rwinlib/libv8/archive/v%s.zip", VERSION), "v8.zip", quiet = TRUE)
+  dir.create("../windows", showWarnings = FALSE)
+  unzip("v8.zip", exdir = "../windows")
+  setwd(LIBDIR)
+  unzip("lib-4.9.3.zip")
+  if(getRversion() >= "3.6.0") unzip("lib.zip")
+  unlink("v8.zip")
+}
diff --git a/tools/ucrtlibs.R b/tools/ucrtlibs.R
deleted file mode 100644
index 702da53..0000000
--- a/tools/ucrtlibs.R
+++ /dev/null
@@ -1,7 +0,0 @@
-# Build against UCRT build of libv8
-if(!file.exists('../windows/ucrt64/include/v8.h')){
-  download.file('https://github.com/jeroen/V8/releases/download/v3.6.0/v8-9.1.269.38-win-ucrt.pkg.tar.xz', "ucrt64.tar.xz", quiet = TRUE)
-  dir.create("../windows", showWarnings = FALSE)
-  untar('ucrt64.tar.xz', exdir = "../windows", tar = 'internal')
-  unlink('ucrt64.tar.xz')
-}
diff --git a/tools/winlibs.R b/tools/winlibs.R
index b95831e..1dda28c 100644
--- a/tools/winlibs.R
+++ b/tools/winlibs.R
@@ -1,13 +1,16 @@
-# Build against mingw-w64 build of libv8
-VERSION <- commandArgs(TRUE)
-LIBDIR <- paste0("../windows/libv8-", VERSION)
-if(!file.exists(paste0(LIBDIR, "/include/v8.h"))){
-  if(getRversion() < "3.3.0") stop("This library requires R 3.3 or newer")
-  download.file(sprintf("https://github.com/rwinlib/libv8/archive/v%s.zip", VERSION), "v8.zip", quiet = TRUE)
+# Download a suitable libv8 build
+if(grepl('Windows Server 2008', osVersion)){
+  stop("Windows Vista/2008 is no longer supported")
+}
+if(!file.exists('../windows/ucrt64/include/v8.h')){
+  cdn <- ifelse(isTRUE(grepl('ucrt', R.version$crt)),
+           'https://github.com/jeroen/V8/releases/download/v3.6.0/v8-9.1.269.38-win-ucrt.pkg.tar.xz',
+           'https://github.com/jeroen/V8/releases/download/v3.6.0/v8-9.1.269.38-win-msvcrt.tar.xz')
+  download.file(cdn, "libv8.tar.xz", quiet = TRUE)
   dir.create("../windows", showWarnings = FALSE)
-  unzip("v8.zip", exdir = "../windows")
-  setwd(LIBDIR)
-  unzip("lib-4.9.3.zip")
-  if(getRversion() >= "3.6.0") unzip("lib.zip")
-  unlink("v8.zip")
+  untar('libv8.tar.xz', exdir = "../windows", tar = 'internal')
+  unlink('libv8.tar.xz')
+  if(isTRUE(grepl('ucrt', R.version$crt))){
+    file.rename("../windows/ucrt64", "../windows/mingw64")
+  }
 }