diff --git a/1k/1kiss.ps1 b/1k/1kiss.ps1
index f6455c4..bd879e7 100644
--- a/1k/1kiss.ps1
+++ b/1k/1kiss.ps1
@@ -236,6 +236,7 @@ $options = @{
     dll    = $false
     u      = $false # whether delete 1kdist cross-platform prebuilt folder: path/to/_x
     dm     = $false # dump compiler preprocessors
+    i      = $false # perform install
 }
 
 $optName = $null
@@ -1837,16 +1838,23 @@ if (!$setupOnly) {
 
                     # step4. build
                     # apply additional build options
-                    $BUILD_ALL_OPTIONS += "--parallel"
-                    $BUILD_ALL_OPTIONS += "$($options.j)"
+                    $BUILD_ALL_OPTIONS += "--parallel", "$($options.j)"
 
+                    if (!$cmake_target) { $cmake_target = $options.t }
+                    if ($cmake_target) { $BUILD_ALL_OPTIONS += '--target', $cmake_target }
+                    $1k.println("BUILD_ALL_OPTIONS=$BUILD_ALL_OPTIONS, Count={0}" -f $BUILD_ALL_OPTIONS.Count)
+
+                    # forward non-cmake args to underlaying build toolchain, must at last
                     if (($cmake_generator -eq 'Xcode') -and !$BUILD_ALL_OPTIONS.Contains('--verbose')) {
                         $BUILD_ALL_OPTIONS += '--', '-quiet'
                     }
-                    $1k.println("BUILD_ALL_OPTIONS=$BUILD_ALL_OPTIONS, Count={0}" -f $BUILD_ALL_OPTIONS.Count)
-
                     $1k.println("cmake --build $BUILD_DIR $BUILD_ALL_OPTIONS")
                     cmake --build $BUILD_DIR $BUILD_ALL_OPTIONS | Out-Host
+
+                    if ($options.i) {
+                        $install_args = @($BUILD_DIR, '--config', $optimize_flag)
+                        cmake --install $install_args | Out-Host
+                    }
                 }
             }
             else {
diff --git a/build.ps1 b/build.ps1
index 6c88737..0236d2e 100644
--- a/build.ps1
+++ b/build.ps1
@@ -19,6 +19,10 @@ function mkdirs($path) {
     }
 }
 
+function sremove($path) {
+    if (Test-Path $path) { Remove-Item $path -Recurse -Force } 
+}
+
 # determine build lib list
 if (!$libs) {
     $libs = @(
@@ -209,6 +213,9 @@ Foreach ($lib_name in $libs) {
         &$patch_script $lib_src
     }
 
+    $install_script = Join-Path $_1k_root "src/$lib_name/install1.ps1"
+    $has_custom_install = (Test-Path $install_script)
+
     # build
     Push-Location $lib_src
     $install_dir = Join-Path $install_root $lib_name
@@ -225,14 +232,19 @@ Foreach ($lib_name in $libs) {
             }
 
             $_config_options += "-DCMAKE_INSTALL_PREFIX=$install_dir"
-
-            if ($compiler_dumped) {
-                &$1k_script -p $target_os -a $target_cpu -xc $_config_options -xb '--target', 'install' @forward_args
+            $evaluated_args = @()
+            if ($build_conf.cb_target) {
+                $evaluated_args += '-t', $build_conf.cb_target
+            }
+            if (!$has_custom_install) {
+                $evaluated_args += '-i'
             }
-            else {
-                &$1k_script -p $target_os -a $target_cpu -xc $_config_options -xb '--target', 'install' @forward_args -dm
+            if (!$compiler_dumped) {
+                $evaluated_args += '-dm'
                 $compiler_dumped = $true
             }
+
+            &$1k_script -p $target_os -a $target_cpu -xc $_config_options @forward_args @evaluated_args
         }
         elseif ($is_gn) {
             &$1k_script -p $target_os -a $target_cpu -xc $_config_options -xt 'gn' -t "$($build_conf.cb_target)" @forward_args
@@ -248,8 +260,7 @@ Foreach ($lib_name in $libs) {
     Pop-Location
 
     # custom install step
-    $install_script = Join-Path $_1k_root "src/$lib_name/install1.ps1"
-    if (Test-Path $install_script) {
+    if ($has_custom_install) {
         &$install_script $install_dir $lib_src
     }
     # clean unnecessary files
diff --git a/src/angle/install1.ps1 b/src/angle/install1.ps1
index 64fd0fc..6deb203 100644
--- a/src/angle/install1.ps1
+++ b/src/angle/install1.ps1
@@ -1,5 +1,5 @@
 $install_dir = $args[0]
-$buildsrc_dir  = $args[1]
+$libsrc_dir  = $args[1]
 
 $buildout = Join-Path $Global:BUILD_DIR '/'
 
@@ -14,7 +14,7 @@ if ($Global:is_win_family) {
     # copy includes
     $inst_inc_dir = Join-Path $install_dir 'include'
     mkdirs $inst_inc_dir
-    Copy-Item -Path $(Join-Path $buildsrc_dir 'include/*') -Destination $inst_inc_dir -Recurse -Force
+    Copy-Item -Path $(Join-Path $libsrc_dir 'include/*') -Destination $inst_inc_dir -Recurse -Force
 
     # copy .lib
     Copy-Item "${buildout}libGLESv2.dll.lib" "${inst_lib_dir}libGLESv2.dll.lib" -Force
diff --git a/src/cares/clean1.ps1 b/src/cares/clean1.ps1
index a123062..75c43a2 100644
--- a/src/cares/clean1.ps1
+++ b/src/cares/clean1.ps1
@@ -3,9 +3,7 @@ $install_dir = $args[0]
 if ((Test-Path $install_dir -PathType Container)) {
     Write-Output "Cleaning ${install_dir}..."
     # Delete files what we don't want
-    Remove-Item "$install_dir/lib/cmake" -Recurse -Force
-    Remove-Item "$install_dir/lib/pkgconfig" -Recurse -Force
-    if (Test-Path "$install_dir/share" -PathType Container) {
-        Remove-Item "$install_dir/share" -Recurse -Force
-    }
+    sremove "$install_dir/lib/cmake"
+    sremove "$install_dir/lib/pkgconfig"
+    sremove "$install_dir/share"
 }
diff --git a/src/curl/clean1.ps1 b/src/curl/clean1.ps1
index f0b9c0a..6552e0b 100644
--- a/src/curl/clean1.ps1
+++ b/src/curl/clean1.ps1
@@ -4,10 +4,10 @@ if ((Test-Path $install_dir -PathType Container)) {
     Write-Output "Cleaning ${install_dir}..."
     # Delete files what we don't want
     if($IsWindows) {
-        Remove-Item "$install_dir\bin\curl-config"
+        sremove "$install_dir\bin\curl-config"
     } else {
-        Remove-Item "$install_dir\bin" -Recurse -Force
+        sremove "$install_dir\bin"
     }
-    Remove-Item "$install_dir\lib\cmake" -Recurse -Force
-    Remove-Item "$install_dir\lib\pkgconfig" -Recurse -Force
+    sremove "$install_dir\lib\cmake"
+    sremove "$install_dir\lib\pkgconfig"
 }
diff --git a/src/jpeg-turbo/clean1.ps1 b/src/jpeg-turbo/clean1.ps1
index 9e5f44a..ae7895f 100644
--- a/src/jpeg-turbo/clean1.ps1
+++ b/src/jpeg-turbo/clean1.ps1
@@ -4,8 +4,8 @@ if ((Test-Path $install_dir -PathType Container)) {
     Write-Output "Cleaning ${install_dir}..."
     # Delete files what we don't want
     # Remove-Item "$install_dir\bin" -recurse
-    Remove-Item "$install_dir\share" -recurse
-    Remove-Item "$install_dir\lib\cmake" -recurse
-    Remove-Item "$install_dir\lib\pkgconfig" -recurse
+    sremove "$install_dir\share"
+    sremove "$install_dir\lib\cmake"
+    sremove "$install_dir\lib\pkgconfig"
     ls -R "$install_dir"
 }
diff --git a/src/llvm/build.yml b/src/llvm/build.yml
index b2ead41..806f7d5 100644
--- a/src/llvm/build.yml
+++ b/src/llvm/build.yml
@@ -1,11 +1,11 @@
 repo: https://github.com/llvm/llvm-project.git
-ver: 16.0.6
+ver: 15.0.7
 tag_prefix: llvmorg-
 tag_dot2ul: false
 cb_tool: cmake
 cb_target: libclang
 targets: win32,linux,osx
 archs: x64,arm64
-options: -S llvm -DLLVM_ENABLE_PROJECTS=clang
+options: -S llvm -DLLVM_ENABLE_PROJECTS=clang -DCMAKE_CXX_STANDARD=17
 options_unix: -DCMAKE_BUILD_TYPE=Release -DCMAKE_PLATFORM_NO_VERSIONED_SONAME=1
-options_msw: -Thost=x64
+options_msw: -Thost=x64 -DCMAKE_C_FLAGS=/source-charset:utf-8 -DCMAKE_CXX_FLAGS=/source-charset:utf-8
diff --git a/src/llvm/clean1.ps1 b/src/llvm/clean1.ps1
index e81069e..5c8b394 100644
--- a/src/llvm/clean1.ps1
+++ b/src/llvm/clean1.ps1
@@ -2,5 +2,9 @@ $install_dir = $args[0]
 
 if ((Test-Path $install_dir -PathType Container)) {
     echo "[windows] Cleaning ${install_dir}..."
+    sremove (Join-Path $install_dir 'include')
+    sremove (Join-Path $install_dir 'lib/*.lib')
+    sremove (Join-Path $install_dir 'lib/*.a')
+    sremove (Join-Path $install_dir 'bin/*.exe')
     ls -R "$install_dir"
 }
diff --git a/src/llvm/install1.ps1 b/src/llvm/install1.ps1
new file mode 100644
index 0000000..81ed3a5
--- /dev/null
+++ b/src/llvm/install1.ps1
@@ -0,0 +1,7 @@
+$install_dir = $args[0]
+# $libsrc_dir  = $args[1]
+
+$artifact_path = @('Release\bin\libclang.dll', 'lib\libclang.so', 'Release\lib\libclang.dylib')[$HOST_OS]
+$install_dest = (Join-Path $install_dir (@('lib', 'bin')[$IsWin]))
+mkdirs $install_dest
+Copy-Item (Join-Path $BUILD_DIR "$artifact_path") $install_dest
\ No newline at end of file
diff --git a/src/luajit/install1.ps1 b/src/luajit/install1.ps1
index db8736f..853a604 100644
--- a/src/luajit/install1.ps1
+++ b/src/luajit/install1.ps1
@@ -1,5 +1,5 @@
 $install_dir = $args[0]
-$buildsrc_dir  = $args[1]
+$libsrc_dir  = $args[1]
 
 if ($IsWindows) {
     # copy prebuilt luajit manually
@@ -8,17 +8,17 @@ if ($IsWindows) {
     mkdir "$install_dir\bin" -Force
     mkdir "$install_dir\bin\jit" -Force
 
-    Copy-Item "$buildsrc_dir\src\lua51.lib" "$install_dir\lib\lua51.lib" -Force
-    Copy-Item "$buildsrc_dir\src\lua51.dll" "$install_dir\bin\lua51.dll" -Force
-    Copy-Item "$buildsrc_dir\src\luajit.exe" "$install_dir\bin\luajit.exe" -Force
-    Copy-Item -Path "$buildsrc_dir\src\jit\*.lua" -Destination "$install_dir\bin\jit" -Recurse -Force
+    Copy-Item "$libsrc_dir\src\lua51.lib" "$install_dir\lib\lua51.lib" -Force
+    Copy-Item "$libsrc_dir\src\lua51.dll" "$install_dir\bin\lua51.dll" -Force
+    Copy-Item "$libsrc_dir\src\luajit.exe" "$install_dir\bin\luajit.exe" -Force
+    Copy-Item -Path "$libsrc_dir\src\jit\*.lua" -Destination "$install_dir\bin\jit" -Recurse -Force
 
-    Copy-Item "$buildsrc_dir\src\lauxlib.h" "$install_dir\include\lauxlib.h" -Force
-    Copy-Item "$buildsrc_dir\src\lua.h" "$install_dir\include\lua.h" -Force
-    Copy-Item "$buildsrc_dir\src\lua.hpp" "$install_dir\include\lua.hpp" -Force
-    Copy-Item "$buildsrc_dir\src\luaconf.h" "$install_dir\include\luaconf.h" -Force
-    Copy-Item "$buildsrc_dir\src\luajit.h" "$install_dir\include\luajit.h" -Force
-    Copy-Item "$buildsrc_dir\src\lualib.h" "$install_dir\include\lualib.h" -Force
+    Copy-Item "$libsrc_dir\src\lauxlib.h" "$install_dir\include\lauxlib.h" -Force
+    Copy-Item "$libsrc_dir\src\lua.h" "$install_dir\include\lua.h" -Force
+    Copy-Item "$libsrc_dir\src\lua.hpp" "$install_dir\include\lua.hpp" -Force
+    Copy-Item "$libsrc_dir\src\luaconf.h" "$install_dir\include\luaconf.h" -Force
+    Copy-Item "$libsrc_dir\src\luajit.h" "$install_dir\include\luajit.h" -Force
+    Copy-Item "$libsrc_dir\src\lualib.h" "$install_dir\include\lualib.h" -Force
 
     echo "[windows] list ${install_dir}..."
     ls -R "$install_dir"
@@ -27,14 +27,14 @@ if ($IsWindows) {
     mkdir "$install_dir/include"
     mkdir "$install_dir/lib"
 
-    cp "$buildsrc_dir/src/libluajit.a" "$install_dir/lib/libluajit.a"
+    cp "$libsrc_dir/src/libluajit.a" "$install_dir/lib/libluajit.a"
 
-    cp "$buildsrc_dir/src/lauxlib.h" "$install_dir/include/lauxlib.h"
-    cp "$buildsrc_dir/src/lua.h" "$install_dir/include/lua.h"
-    cp "$buildsrc_dir/src/lua.hpp" "$install_dir/include/lua.hpp"
-    cp "$buildsrc_dir/src/luaconf.h" "$install_dir/include/luaconf.h"
-    cp "$buildsrc_dir/src/luajit.h" "$install_dir/include/luajit.h"
-    cp "$buildsrc_dir/src/lualib.h" "$install_dir/include/lualib.h"
+    cp "$libsrc_dir/src/lauxlib.h" "$install_dir/include/lauxlib.h"
+    cp "$libsrc_dir/src/lua.h" "$install_dir/include/lua.h"
+    cp "$libsrc_dir/src/lua.hpp" "$install_dir/include/lua.hpp"
+    cp "$libsrc_dir/src/luaconf.h" "$install_dir/include/luaconf.h"
+    cp "$libsrc_dir/src/luajit.h" "$install_dir/include/luajit.h"
+    cp "$libsrc_dir/src/lualib.h" "$install_dir/include/lualib.h"
 
     echo "[unix] list ${install_dir}..."
 }
diff --git a/src/zlib/clean1.ps1 b/src/zlib/clean1.ps1
index 7d25912..b115c9a 100644
--- a/src/zlib/clean1.ps1
+++ b/src/zlib/clean1.ps1
@@ -3,5 +3,5 @@ $install_dir = $args[0]
 if ((Test-Path $install_dir -PathType Container)) {
     Write-Output "Cleaning ${install_dir}..."
     # Delete files what we don't want
-    Remove-Item "$install_dir/share" -Recurse -Force
+    sremove "$install_dir/share"
 }