diff --git a/bin/phpsdk_buildtree.bat b/bin/phpsdk_buildtree.bat
index 790b82b..21e5800 100644
--- a/bin/phpsdk_buildtree.bat
+++ b/bin/phpsdk_buildtree.bat
@@ -27,6 +27,9 @@ if "%PHP_SDK_ARCH%" NEQ "" (
 		MD %_%\%%i\x64\deps\bin
 		MD %_%\%%i\x64\deps\lib
 		MD %_%\%%i\x64\deps\include
+		MD %_%\%%i\arm64\deps\bin
+		MD %_%\%%i\arm64\deps\lib
+		MD %_%\%%i\arm64\deps\include
 	)
 )
 
diff --git a/bin/phpsdk_deps.php b/bin/phpsdk_deps.php
index e161ff3..31869c9 100644
--- a/bin/phpsdk_deps.php
+++ b/bin/phpsdk_deps.php
@@ -180,7 +180,7 @@ function usage(int $code = -1)
 	echo "Usage: ", PHP_EOL, PHP_EOL;
 	echo "Configuration:", PHP_EOL;
 	echo "  -b --branch    Branch name, eg. 7.0, 7.1, etc. If omited, several guess methods apply.", PHP_EOL;
-	echo "  -a --arch      Architecture, x86 or x64. If omited, cl.exe is used to guess.", PHP_EOL;
+	echo "  -a --arch      Architecture, x86 or x64 or arm64. If omited, cl.exe is used to guess.", PHP_EOL;
 	echo "  -t --crt       CRT, marked by the corresponding VC++ version, eg. vc11, vc14, etc.", PHP_EOL;
 	echo "  -s --stability One of stable or staging.", PHP_EOL, PHP_EOL;
 	echo "Commands:", PHP_EOL;
diff --git a/bin/phpsdk_dumpenv.bat b/bin/phpsdk_dumpenv.bat
index b2c0e49..7d44df5 100644
--- a/bin/phpsdk_dumpenv.bat
+++ b/bin/phpsdk_dumpenv.bat
@@ -12,18 +12,8 @@ echo.
 call %PHP_SDK_BIN_PATH%\phpsdk_version.bat
 echo.
 
-if "%PHP_SDK_OS_ARCH%"=="x64" (
-	echo OS architecture:    64-bit 
-) else (
-	echo OS architecture:    32-bit 
-)
-
-if "%PHP_SDK_ARCH%"=="x64" (
-	echo Build architecture: 64-bit 
-) else (
-	echo Build architecture: 32-bit 
-)
-
+echo OS architecture:    %PHP_SDK_OS_ARCH% 
+echo Build architecture: %PHP_SDK_ARCH% 
 echo Visual C++:         %PHP_SDK_VC_TOOLSET_VER%
 echo PHP-SDK path:       %PHP_SDK_ROOT_PATH%
 
diff --git a/bin/phpsdk_setshell.bat b/bin/phpsdk_setshell.bat
index aeb5b58..cd6a9ad 100644
--- a/bin/phpsdk_setshell.bat
+++ b/bin/phpsdk_setshell.bat
@@ -44,32 +44,62 @@ if 14 gtr %TMP_CHK% (
 set PHP_SDK_VS_NUM=%TMP_CHK%
 set TMP_CHK=
 
-if /i not "%2"=="x64" (
-	if /i not "%2"=="x86" (
-		echo Unsupported arch "%2"
-		goto out_error
-	)
+rem check target arch
+if "%2"=="x86" set PHP_SDK_ARCH=%2
+if "%2"=="x64" set PHP_SDK_ARCH=%2
+if "%2"=="x86_64" set PHP_SDK_ARCH=x64
+if "%2"=="amd64" set PHP_SDK_ARCH=x64
+if "%2"=="arm64" set PHP_SDK_ARCH=%2
+if "%PHP_SDK_ARCH%"=="" (
+	echo Unsupported target arch %2 >&2
+	goto out_error
 )
 
-set PHP_SDK_ARCH=%2
-
 rem check OS arch
-set TMPKEY=HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion
-reg query "%TMPKEY%" /v "ProgramFilesDir (x86)" >nul 2>nul
-if not errorlevel 1 (
-	set PHP_SDK_OS_ARCH=x64
-) else (
-	if /i "%PHP_SDK_ARCH%"=="x64" (
-		echo 32-bit OS detected, native 64-bit toolchain is unavailable.
-		goto out_error
-	)
-	set PHP_SDK_OS_ARCH=x86
+rem todo: allow user choose host sdk arch (i.e. x64 target can be compiled at x64(native) or x86(cross))
+for /f "usebackq tokens=1*" %%i in (`wmic cpu get Architecture /value /format:table ^| findstr /r "[1234567890][1234567890]*"`) do (
+	set PHP_SDK_OS_ARCH_NUM=%%i
+)
+
+goto os_arch_cases
+:os_arch_error
+echo Unsupported OS arch %PHP_SDK_OS_ARCH% >&2
+goto out_error
+
+:os_arch_cases
+if "%PHP_SDK_OS_ARCH_NUM%"=="0" set PHP_SDK_OS_ARCH=x86
+if "%PHP_SDK_OS_ARCH_NUM%"=="1" (set PHP_SDK_OS_ARCH=mips && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="2" (set PHP_SDK_OS_ARCH=alpha && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="3" (set PHP_SDK_OS_ARCH=ppc && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="4" (set PHP_SDK_OS_ARCH=shx && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="5" (set PHP_SDK_OS_ARCH=arm32 && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="6" (set PHP_SDK_OS_ARCH=ia64 && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="7" (set PHP_SDK_OS_ARCH=alpha64 && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="8" (set PHP_SDK_OS_ARCH=msil && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="9" set PHP_SDK_OS_ARCH=x64
+rem wow64
+if "%PHP_SDK_OS_ARCH_NUM%"=="10" set PHP_SDK_OS_ARCH=x86
+if "%PHP_SDK_OS_ARCH_NUM%"=="11" (set PHP_SDK_OS_ARCH=neutral && goto os_arch_error)
+if "%PHP_SDK_OS_ARCH_NUM%"=="12" set PHP_SDK_OS_ARCH=arm64
+if "%PHP_SDK_OS_ARCH_NUM%"=="13" (set PHP_SDK_OS_ARCH=arm32 && goto os_arch_error)
+rem woa64
+if "%PHP_SDK_OS_ARCH_NUM%"=="14" set PHP_SDK_OS_ARCH=x86
+if "%PHP_SDK_OS_ARCH%"=="" (
+	goto os_arch_error
 )
-set TMPKEY=
+
+set PHP_SDK_OS_ARCH_NUM=
+
+rem cross compile is ok, so we donot need this
+rem if not /i "%PHP_SDK_ARCH%"=="PHP_SDK_OS_ARCH" (
+rem 	echo 32-bit OS detected, native 64-bit toolchain is unavailable.
+rem 	goto out_error
+rem )
 
 rem get vc base dir
 if 15 gtr %PHP_SDK_VS_NUM% (
-	if /i "%PHP_SDK_OS_ARCH%"=="x64" (
+	rem for arch other than x86, use WOW6432
+	if /i not "%PHP_SDK_OS_ARCH%"=="x86" (
 		set TMPKEY=HKLM\SOFTWARE\Wow6432Node\Microsoft\VisualStudio\%PHP_SDK_VS:~2%.0\Setup\VC
 	) else (
 		set TMPKEY=HKLM\SOFTWARE\Microsoft\VisualStudio\%PHP_SDK_VS:~2%.0\Setup\VC
@@ -85,16 +115,20 @@ if 15 gtr %PHP_SDK_VS_NUM% (
 	set /a PHP_SDK_VS_RANGE=PHP_SDK_VS_NUM + 1
 	set PHP_SDK_VS_RANGE="[%PHP_SDK_VS_NUM%,!PHP_SDK_VS_RANGE%!)"
 
-	for /f "tokens=1* delims=: " %%a in ('%~dp0\vswhere -nologo -version !PHP_SDK_VS_RANGE! -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath -format text') do (
+	set APPEND=x86.x64
+	if /i "%PHP_SDK_OS_ARCH%"=="arm64" (
+		set APPEND=ARM64
+	)
+	for /f "tokens=1* delims=: " %%a in ('%~dp0\vswhere -nologo -version !PHP_SDK_VS_RANGE! -requires Microsoft.VisualStudio.Component.VC.Tools.!APPEND! -property installationPath -format text') do (
 		set PHP_SDK_VC_DIR=%%b\VC
 	)
 	if not exist "!PHP_SDK_VC_DIR!" (
-		for /f "tokens=1* delims=: " %%a in ('%~dp0\vswhere -nologo -version !PHP_SDK_VS_RANGE! -products Microsoft.VisualStudio.Product.BuildTools -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath -format text') do (
+		for /f "tokens=1* delims=: " %%a in ('%~dp0\vswhere -nologo -version !PHP_SDK_VS_RANGE! -products Microsoft.VisualStudio.Product.BuildTools -requires Microsoft.VisualStudio.Component.VC.Tools.!APPEND! -property installationPath -format text') do (
 			set PHP_SDK_VC_DIR=%%b\VC
 		)
 		if not exist "!PHP_SDK_VC_DIR!" (
 			rem check for a preview release
-			for /f "tokens=1* delims=: " %%a in ('%~dp0\vswhere -nologo -version !PHP_SDK_VS_RANGE! -prerelease -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath -format text') do (
+			for /f "tokens=1* delims=: " %%a in ('%~dp0\vswhere -nologo -version !PHP_SDK_VS_RANGE! -prerelease -requires Microsoft.VisualStudio.Component.VC.Tools.!APPEND! -property installationPath -format text') do (
 				set PHP_SDK_VC_DIR=%%b\VC
 			)
 			if not exist "!PHP_SDK_VC_DIR!" (
@@ -105,13 +139,15 @@ if 15 gtr %PHP_SDK_VS_NUM% (
 	)
 	set VSCMD_ARG_no_logo=nologo
 )
+set APPEND=
 set TMPKEY=
 set PHP_SDK_VS_RANGE=
 
 if 15 gtr %PHP_SDK_VS_NUM% (
 	rem get sdk dir
 	rem if 10.0 is available, it's ok
-	if /i "%PHP_SDK_OS_ARCH%"=="x64" (
+	rem for arch other than x86, use WOW6432
+	if /i not "%PHP_SDK_OS_ARCH%"=="x86" (
 		set TMPKEY=HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Microsoft SDKs\Windows\v10.0
 	) else (
 		set TMPKEY=HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SDKs\Windows\v10.0
@@ -125,7 +161,8 @@ if 15 gtr %PHP_SDK_VS_NUM% (
 	)
 
 	rem Otherwise 8.1 should be available anyway
-	if /i "%PHP_SDK_OS_ARCH%"=="x64" (
+	rem for arch other than x86, use WOW6432
+	if /i not "%PHP_SDK_OS_ARCH%"=="x86" (
 		set TMPKEY=HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Microsoft SDKs\Windows\v8.1
 	) else (
 		set TMPKEY=HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SDKs\Windows\v8.1
@@ -143,18 +180,28 @@ if 15 gtr %PHP_SDK_VS_NUM% (
 )
 
 if /i "%PHP_SDK_ARCH%"=="x64" (
-	if 15 gtr %PHP_SDK_VS_NUM% (
-		set PHP_SDK_VS_SHELL_CMD="!PHP_SDK_VC_DIR!\vcvarsall.bat" amd64
-	) else (
-		set PHP_SDK_VS_SHELL_CMD="!PHP_SDK_VC_DIR!\Auxiliary\Build\vcvarsall.bat" amd64
-	)
+	set TARGET_ARCH_NAME=amd64
 ) else (
-	if 15 gtr %PHP_SDK_VS_NUM% (
-		set PHP_SDK_VS_SHELL_CMD="!PHP_SDK_VC_DIR!\vcvarsall.bat" x86
-	) else (
-		set PHP_SDK_VS_SHELL_CMD="!PHP_SDK_VC_DIR!\Auxiliary\Build\vcvarsall.bat" x86
-	)
+	set TARGET_ARCH_NAME=%PHP_SDK_ARCH%
+)
+
+if /i "%PHP_SDK_OS_ARCH%"=="x64" (
+	set HOST_ARCH_NAME=amd64
+) else (
+	set HOST_ARCH_NAME=%PHP_SDK_ARCH%
+)
+
+if "%HOST_ARCH_NAME%"=="%TARGET_ARCH_NAME%" (
+	set VCVARSALL_ARCH_NAME=%HOST_ARCH_NAME%
+) else (
+	set VCVARSALL_ARCH_NAME=%HOST_ARCH_NAME%_%TARGET_ARCH_NAME%
+)
+if 15 gtr %PHP_SDK_VS_NUM% (
+	set PHP_SDK_VS_SHELL_CMD="!PHP_SDK_VC_DIR!\vcvarsall.bat" !VCVARSALL_ARCH_NAME!
+) else (
+	set PHP_SDK_VS_SHELL_CMD="!PHP_SDK_VC_DIR!\Auxiliary\Build\vcvarsall.bat" !VCVARSALL_ARCH_NAME!
 )
+set VCVARSALL_ARCH_NAME=
 
 rem echo Visual Studio VC path %PHP_SDK_VC_DIR%
 rem echo Windows SDK path %PHP_SDK_WIN_SDK_DIR%
diff --git a/lib/php/libsdk/SDK/Config.php b/lib/php/libsdk/SDK/Config.php
index c116ac9..e6b6d08 100644
--- a/lib/php/libsdk/SDK/Config.php
+++ b/lib/php/libsdk/SDK/Config.php
@@ -47,8 +47,8 @@ public static function setCurrentArchName(string $arch) : void
 	{/*{{{*/
 		$arch = strtolower($arch);
 
-		if ("x64" != $arch && "x86" != $arch) {
-			throw new Exception("Unknown arch keyword, either x86 or x64 is accepted");
+		if ("x64" != $arch && "x86" != $arch && "arm64" != $arch) {
+			throw new Exception("Unknown arch keyword, x86 or x64 or arm64 is accepted");
 		}
 
 		self::$currentArchName = $arch;
@@ -72,6 +72,8 @@ public static function getCurrentArchName() : string
 					self::setCurrentArchName("x64");
 				} elseif (preg_match(",x86,", $out[0])) {
 					self::setCurrentArchName("x86");
+				} elseif (preg_match(",arm64,", $out[0])) {
+					self::setCurrentArchName("arm64");
 				} else {
 					throw new Exception("Couldn't determine Arch.");
 				}
@@ -146,7 +148,7 @@ public static function getKnownBranches() : array
 			$tmp = $fetcher->getByUri(self::$depsBaseUri . "/series/");
 			if (false !== $tmp) {
 				$data = array();
-				if (preg_match_all(",/packages-(.+)-(v[cs]\d+)-(x86|x64)-(stable|staging)\.txt,U", $tmp, $m, PREG_SET_ORDER)) {
+				if (preg_match_all(",/packages-(.+)-(v[cs]\d+)-(x86|x64|arm64)-(stable|staging)\.txt,U", $tmp, $m, PREG_SET_ORDER)) {
 					foreach ($m as $b) {
 						if (!isset($data[$b[1]])) {
 							$data[$b[1]] = array();
diff --git a/pgo/tpl/php/phpsdk_pgo.json b/pgo/tpl/php/phpsdk_pgo.json
index 5d21d23..b7362eb 100644
--- a/pgo/tpl/php/phpsdk_pgo.json
+++ b/pgo/tpl/php/phpsdk_pgo.json
@@ -14,6 +14,12 @@
 	{
 		"cache": {
 			"ini": {
+				"arm64": {
+					"opcache.memory_consumption": 256,
+					"opcache.interned_strings_buffer": 16,
+					"opcache.max_accelerated_files": 8000,
+					"opcache.jit_buffer_size": "32M"
+				},
 				"x64": {
 					"opcache.memory_consumption": 256,
 					"opcache.interned_strings_buffer": 16,