diff --git a/src/Package/Artifact/llvm_compiler_rt.php b/src/Package/Artifact/llvm_compiler_rt.php
index 974b9d57..166500b9 100644
--- a/src/Package/Artifact/llvm_compiler_rt.php
+++ b/src/Package/Artifact/llvm_compiler_rt.php
@@ -7,6 +7,7 @@ namespace Package\Artifact;
 use StaticPHP\Artifact\ArtifactDownloader;
 use StaticPHP\Artifact\Downloader\DownloadResult;
 use StaticPHP\Artifact\Downloader\Type\CheckUpdateResult;
+use StaticPHP\Artifact\Downloader\Type\GitHubTokenSetupTrait;
 use StaticPHP\Attribute\Artifact\AfterBinaryExtract;
 use StaticPHP\Attribute\Artifact\CustomBinary;
 use StaticPHP\Attribute\Artifact\CustomBinaryCheckUpdate;
@@ -21,6 +22,8 @@ use StaticPHP\Runtime\SystemTarget;
  */
 class llvm_compiler_rt
 {
+    use GitHubTokenSetupTrait;
+
     #[CustomBinary('llvm-compiler-rt', [
         'linux-x86_64',
         'linux-aarch64',
@@ -34,7 +37,7 @@ class llvm_compiler_rt
         $tarball = "compiler-rt-{$llvmVersion}.src.tar.xz";
         $url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-{$llvmVersion}/{$tarball}";
         $tarballPath = DOWNLOAD_PATH . '/' . $tarball;
-        default_shell()->executeCurlDownload($url, $tarballPath, retries: $downloader->getRetry());
+        default_shell()->executeCurlDownload($url, $tarballPath, headers: $this->getGitHubTokenHeaders(), retries: $downloader->getRetry());
         return DownloadResult::archive($tarball, ['url' => $url, 'version' => $llvmVersion], extract: '{source_path}/llvm-compiler-rt', verified: false, version: $llvmVersion);
     }
 
diff --git a/src/Package/Artifact/llvm_tools.php b/src/Package/Artifact/llvm_tools.php
index 5dd26214..3be55a93 100644
--- a/src/Package/Artifact/llvm_tools.php
+++ b/src/Package/Artifact/llvm_tools.php
@@ -7,6 +7,7 @@ namespace Package\Artifact;
 use StaticPHP\Artifact\ArtifactDownloader;
 use StaticPHP\Artifact\Downloader\DownloadResult;
 use StaticPHP\Artifact\Downloader\Type\CheckUpdateResult;
+use StaticPHP\Artifact\Downloader\Type\GitHubTokenSetupTrait;
 use StaticPHP\Attribute\Artifact\AfterBinaryExtract;
 use StaticPHP\Attribute\Artifact\CustomBinary;
 use StaticPHP\Attribute\Artifact\CustomBinaryCheckUpdate;
@@ -17,6 +18,8 @@ use StaticPHP\Package\PackageBuilder;
 
 class llvm_tools
 {
+    use GitHubTokenSetupTrait;
+
     public const array TOOLS = ['llvm-objcopy', 'llvm-strip', 'llvm-profdata'];
 
     #[CustomBinary('llvm-tools', [
@@ -32,7 +35,7 @@ class llvm_tools
         $tarball = "llvm-project-{$llvmVersion}.src.tar.xz";
         $url = "https://github.com/llvm/llvm-project/releases/download/llvmorg-{$llvmVersion}/{$tarball}";
         $tarballPath = DOWNLOAD_PATH . '/' . $tarball;
-        default_shell()->executeCurlDownload($url, $tarballPath, retries: $downloader->getRetry());
+        default_shell()->executeCurlDownload($url, $tarballPath, headers: $this->getGitHubTokenHeaders(), retries: $downloader->getRetry());
         return DownloadResult::archive($tarball, ['url' => $url, 'version' => $llvmVersion], extract: '{source_path}/llvm-tools', verified: false, version: $llvmVersion);
     }
 
diff --git a/src/StaticPHP/Artifact/Artifact.php b/src/StaticPHP/Artifact/Artifact.php
index f209006d..12b81a89 100644
--- a/src/StaticPHP/Artifact/Artifact.php
+++ b/src/StaticPHP/Artifact/Artifact.php
@@ -27,12 +27,18 @@ class Artifact
     /** @var null|callable Bind custom source fetcher callback */
     protected mixed $custom_source_callback = null;
 
+    /** @var null|string Display label describing where the custom source callback came from */
+    protected ?string $custom_source_callback_origin = null;
+
     /** @var null|callable Bind custom source check-update callback */
     protected mixed $custom_source_check_update_callback = null;
 
     /** @var array<string, callable> Bind custom binary fetcher callbacks */
     protected mixed $custom_binary_callbacks = [];
 
+    /** @var array<string, string> Display label per platform describing where the custom binary callback came from */
+    protected array $custom_binary_callback_origins = [];
+
     /** @var array<string, callable> Bind custom binary check-update callbacks */
     protected array $custom_binary_check_update_callbacks = [];
 
@@ -411,10 +417,13 @@ class Artifact
 
     /**
      * Set custom source fetcher callback.
+     *
+     * @param string $origin Short label shown in progress output (e.g. 'package downloader', 'custom url')
      */
-    public function setCustomSourceCallback(callable $callback): void
+    public function setCustomSourceCallback(callable $callback, string $origin = 'package downloader'): void
     {
         $this->custom_source_callback = $callback;
+        $this->custom_source_callback_origin = $origin;
     }
 
     public function getCustomSourceCallback(): ?callable
@@ -422,6 +431,11 @@ class Artifact
         return $this->custom_source_callback ?? null;
     }
 
+    public function getCustomSourceCallbackOrigin(): ?string
+    {
+        return $this->custom_source_callback_origin;
+    }
+
     /**
      * Set custom source check-update callback.
      */
@@ -456,11 +470,19 @@ class Artifact
      *
      * @param string   $target_os Target OS platform string (e.g. linux-x86_64)
      * @param callable $callback  Custom binary fetcher callback
+     * @param string   $origin    Short label shown in progress output (e.g. 'package downloader')
      */
-    public function setCustomBinaryCallback(string $target_os, callable $callback): void
+    public function setCustomBinaryCallback(string $target_os, callable $callback, string $origin = 'package downloader'): void
     {
         ConfigValidator::validatePlatformString($target_os);
         $this->custom_binary_callbacks[$target_os] = $callback;
+        $this->custom_binary_callback_origins[$target_os] = $origin;
+    }
+
+    public function getCustomBinaryCallbackOrigin(): ?string
+    {
+        $current_platform = SystemTarget::getCurrentPlatformString();
+        return $this->custom_binary_callback_origins[$current_platform] ?? null;
     }
 
     /**
diff --git a/src/StaticPHP/Artifact/ArtifactDownloader.php b/src/StaticPHP/Artifact/ArtifactDownloader.php
index 83e80f31..4b5a399a 100644
--- a/src/StaticPHP/Artifact/ArtifactDownloader.php
+++ b/src/StaticPHP/Artifact/ArtifactDownloader.php
@@ -554,8 +554,8 @@ class ArtifactDownloader
                 $instance = null;
                 $call = $this->downloaders[$item['config']['type']] ?? null;
                 $type_display_name = match (true) {
-                    $item['lock'] === 'source' && ($callback = $artifact->getCustomSourceCallback()) !== null => 'user defined source downloader',
-                    $item['lock'] === 'binary' && ($callback = $artifact->getCustomBinaryCallback()) !== null => 'user defined binary downloader',
+                    $item['lock'] === 'source' && $artifact->getCustomSourceCallback() !== null => $artifact->getCustomSourceCallbackOrigin() ?? 'source package downloader',
+                    $item['lock'] === 'binary' && $artifact->getCustomBinaryCallback() !== null => $artifact->getCustomBinaryCallbackOrigin() ?? 'binary package downloader',
                     default => SPC_DOWNLOAD_TYPE_DISPLAY_NAME[$item['config']['type']] ?? $item['config']['type'],
                 };
                 $try_h = $try ? 'Try downloading' : 'Downloading';
@@ -838,21 +838,21 @@ class ArtifactDownloader
             if (isset($this->artifacts[$artifact_name])) {
                 $this->artifacts[$artifact_name]->setCustomSourceCallback(function (ArtifactDownloader $downloader) use ($artifact_name, $custom_url) {
                     return (new Url())->download($artifact_name, ['url' => $custom_url], $downloader);
-                });
+                }, 'custom url');
             }
         }
         foreach ($this->custom_gits as $artifact_name => [$branch, $git_url]) {
             if (isset($this->artifacts[$artifact_name])) {
                 $this->artifacts[$artifact_name]->setCustomSourceCallback(function (ArtifactDownloader $downloader) use ($artifact_name, $branch, $git_url) {
                     return (new Git())->download($artifact_name, ['rev' => $branch, 'url' => $git_url], $downloader);
-                });
+                }, 'custom git');
             }
         }
         foreach ($this->custom_locals as $artifact_name => $local_path) {
             if (isset($this->artifacts[$artifact_name])) {
                 $this->artifacts[$artifact_name]->setCustomSourceCallback(function (ArtifactDownloader $downloader) use ($artifact_name, $local_path) {
                     return (new LocalDir())->download($artifact_name, ['dirname' => $local_path], $downloader);
-                });
+                }, 'custom local dir');
             }
         }
     }