diff --git a/config/artifact/ncurses.yml b/config/artifact/ncurses.yml
index 173d4c32..8d39e81b 100644
--- a/config/artifact/ncurses.yml
+++ b/config/artifact/ncurses.yml
@@ -4,5 +4,5 @@ ncurses:
       - COPYING
   source:
     type: filelist
-    url: 'https://ftp.gnu.org/pub/gnu/ncurses/'
+    url: 'https://ftpmirror.gnu.org/gnu/ncurses/'
     regex: '/href="(?<file>ncurses-(?<version>[^"]+)\.tar\.gz)"/'
diff --git a/config/env.ini b/config/env.ini
index 65fad077..c3f01672 100644
--- a/config/env.ini
+++ b/config/env.ini
@@ -146,7 +146,7 @@ AR=${SPC_DEFAULT_AR}
 RANLIB=${SPC_DEFAULT_RANLIB}
 LD=${SPC_DEFAULT_LD}
 ; default compiler flags, used in CMake toolchain file, openssl and pkg-config build
-SPC_DEFAULT_CFLAGS="--target=${MAC_ARCH}-apple-darwin -O3 -fno-plt -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -ffunction-sections -fdata-sections"
+SPC_DEFAULT_CFLAGS="--target=${MAC_ARCH}-apple-darwin -O3 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -ffunction-sections -fdata-sections"
 SPC_DEFAULT_CXXFLAGS="${SPC_DEFAULT_CFLAGS}"
 SPC_DEFAULT_LDFLAGS="-Wl,-dead_strip"
 ; phpmicro patches, for more info, see: https://github.com/easysoft/phpmicro/tree/master/patches
diff --git a/config/pkg/lib/gettext.yml b/config/pkg/lib/gettext.yml
index 58f541f8..04743033 100644
--- a/config/pkg/lib/gettext.yml
+++ b/config/pkg/lib/gettext.yml
@@ -3,7 +3,7 @@ gettext:
   artifact:
     source:
       type: filelist
-      url: 'https://ftp.gnu.org/pub/gnu/gettext/'
+      url: 'https://ftpmirror.gnu.org/gnu/gettext/'
       regex: '/href="(?<file>gettext-(?<version>[^"]+)\.tar\.xz)"/'
     metadata:
       license-files: [gettext-runtime/intl/COPYING.LIB]
diff --git a/config/pkg/lib/gmp.yml b/config/pkg/lib/gmp.yml
index c1469774..80303056 100644
--- a/config/pkg/lib/gmp.yml
+++ b/config/pkg/lib/gmp.yml
@@ -3,7 +3,7 @@ gmp:
   artifact:
     source:
       type: filelist
-      url: 'https://ftp.gnu.org/gnu/gmp/'
+      url: 'https://ftpmirror.gnu.org/gnu/gmp/'
       regex: '/href="(?<file>gmp-(?<version>[^"]+)\.tar\.xz)"/'
     source-mirror:
       type: url
diff --git a/config/pkg/lib/idn2.yml b/config/pkg/lib/idn2.yml
index cef2a149..3b597b4d 100644
--- a/config/pkg/lib/idn2.yml
+++ b/config/pkg/lib/idn2.yml
@@ -3,7 +3,7 @@ idn2:
   artifact:
     source:
       type: filelist
-      url: 'https://ftp.gnu.org/gnu/libidn/'
+      url: 'https://ftpmirror.gnu.org/gnu/libidn/'
       regex: '/href="(?<file>libidn2-(?<version>[^"]+)\.tar\.gz)"/'
     metadata:
       license-files: [COPYING.LESSERv3]
diff --git a/config/pkg/lib/libiconv.yml b/config/pkg/lib/libiconv.yml
index 58cd77b0..2893679c 100644
--- a/config/pkg/lib/libiconv.yml
+++ b/config/pkg/lib/libiconv.yml
@@ -3,7 +3,7 @@ libiconv:
   artifact:
     source:
       type: filelist
-      url: 'https://ftp.gnu.org/gnu/libiconv/'
+      url: 'https://ftpmirror.gnu.org/gnu/libiconv/'
       regex: '/href="(?<file>libiconv-(?<version>[^"]+)\.tar\.gz)"/'
     metadata:
       license-files: [COPYING.LIB]
diff --git a/config/pkg/lib/libunistring.yml b/config/pkg/lib/libunistring.yml
index 13a66d42..5a78fa14 100644
--- a/config/pkg/lib/libunistring.yml
+++ b/config/pkg/lib/libunistring.yml
@@ -3,7 +3,7 @@ libunistring:
   artifact:
     source:
       type: filelist
-      url: 'https://ftp.gnu.org/gnu/libunistring/'
+      url: 'https://ftpmirror.gnu.org/gnu/libunistring/'
       regex: '/href="(?<file>libunistring-(?<version>[^"]+)\.tar\.gz)"/'
     metadata:
       license-files: [COPYING.LIB]
diff --git a/config/pkg/lib/readline.yml b/config/pkg/lib/readline.yml
index 0cb80b00..2dd25e49 100644
--- a/config/pkg/lib/readline.yml
+++ b/config/pkg/lib/readline.yml
@@ -3,7 +3,7 @@ readline:
   artifact:
     source:
       type: filelist
-      url: 'https://ftp.gnu.org/pub/gnu/readline/'
+      url: 'https://ftpmirror.gnu.org/gnu/readline/'
       regex: '/href="(?<file>readline-(?<version>[^"]+)\.tar\.gz)"/'
     metadata:
       license-files: [COPYING]
diff --git a/src/StaticPHP/Artifact/Artifact.php b/src/StaticPHP/Artifact/Artifact.php
index 8e2166d1..f209006d 100644
--- a/src/StaticPHP/Artifact/Artifact.php
+++ b/src/StaticPHP/Artifact/Artifact.php
@@ -331,7 +331,7 @@ class Artifact
     public function getSourceRoot(): string
     {
         if (isset($this->config['metadata']['source-root'])) {
-            return $this->getSourceDir() . '/' . ltrim($this->config['metadata']['source-root'], '/');
+            return FileSystem::convertPath($this->getSourceDir() . '/' . ltrim($this->config['metadata']['source-root'], '/'));
         }
         return $this->getSourceDir();
     }
diff --git a/src/StaticPHP/Artifact/ArtifactCache.php b/src/StaticPHP/Artifact/ArtifactCache.php
index 5a2c8bac..2b0c8b54 100644
--- a/src/StaticPHP/Artifact/ArtifactCache.php
+++ b/src/StaticPHP/Artifact/ArtifactCache.php
@@ -223,8 +223,8 @@ class ArtifactCache
     public function getCacheFullPath(array $cache_info): string
     {
         return match ($cache_info['cache_type']) {
-            'archive', 'file' => DOWNLOAD_PATH . '/' . $cache_info['filename'],
-            'git' => DOWNLOAD_PATH . '/' . $cache_info['dirname'],
+            'archive', 'file' => FileSystem::convertPath(DOWNLOAD_PATH . '/' . $cache_info['filename']),
+            'git' => FileSystem::convertPath(DOWNLOAD_PATH . '/' . $cache_info['dirname']),
             'local' => $cache_info['dirname'], // local dirname is absolute path
             default => throw new SPCInternalException("Unknown cache type: {$cache_info['cache_type']}"),
         };
diff --git a/src/StaticPHP/Util/System/WindowsUtil.php b/src/StaticPHP/Util/System/WindowsUtil.php
index 40637262..3e17b4d2 100644
--- a/src/StaticPHP/Util/System/WindowsUtil.php
+++ b/src/StaticPHP/Util/System/WindowsUtil.php
@@ -54,6 +54,7 @@ class WindowsUtil
         }
         $args = [
             '-latest',
+            '-products', '*',
             '-format', 'json',
             '-requires', 'Microsoft.VisualStudio.Component.VC.Tools.x86.x64',
         ];
diff --git a/tests/StaticPHP/Artifact/ArtifactTest.php b/tests/StaticPHP/Artifact/ArtifactTest.php
index e1cb8ccd..0effb109 100644
--- a/tests/StaticPHP/Artifact/ArtifactTest.php
+++ b/tests/StaticPHP/Artifact/ArtifactTest.php
@@ -254,11 +254,16 @@ class ArtifactTest extends TestCase
         ApplicationContext::initialize();
         ApplicationContext::set(ArtifactCache::class, $cache);
 
+        // Use a platform-appropriate absolute path: a Unix-style /tmp/... isn't
+        // absolute on Windows (no drive letter), so the test would otherwise
+        // fall through into the SOURCE_PATH-prefixed branch on Windows.
+        $extract = DIRECTORY_SEPARATOR === '\\' ? 'C:\tmp\my-pkg-extract' : '/tmp/my-pkg-extract';
+
         $artifact = new Artifact('my-pkg', [
-            'source' => ['type' => 'url', 'url' => 'https://example.com/file.tar.gz', 'extract' => '/tmp/my-pkg-extract'],
+            'source' => ['type' => 'url', 'url' => 'https://example.com/file.tar.gz', 'extract' => $extract],
         ]);
 
-        $expected = str_replace(['/', '\\'], DIRECTORY_SEPARATOR, '/tmp/my-pkg-extract');
+        $expected = str_replace(['/', '\\'], DIRECTORY_SEPARATOR, $extract);
         $this->assertSame($expected, $artifact->getSourceDir());
     }
 
@@ -703,11 +708,7 @@ class ArtifactTest extends TestCase
             'Windows' => 'windows',
             default => 'linux',
         };
-        $arch = php_uname('m');
-        if ($arch === 'arm64') {
-            $arch = 'aarch64';
-        }
-        return "{$os}-{$arch}";
+        return "{$os}-" . arch2gnu(php_uname('m'));
     }
 
     private function injectArtifactConfig(string $name, array $config): void