diff --git a/lib/composer/composer/ClassLoader.php b/lib/composer/composer/ClassLoader.php
index a72151c77c8eb..7824d8f7eafe8 100644
--- a/lib/composer/composer/ClassLoader.php
+++ b/lib/composer/composer/ClassLoader.php
@@ -45,35 +45,34 @@ class ClassLoader
     /** @var \Closure(string):void */
     private static $includeFile;
 
-    /** @var ?string */
+    /** @var string|null */
     private $vendorDir;
 
     // PSR-4
     /**
-     * @var array[]
-     * @psalm-var array<string, array<string, int>>
+     * @var array<string, array<string, int>>
      */
     private $prefixLengthsPsr4 = array();
     /**
-     * @var array[]
-     * @psalm-var array<string, array<int, string>>
+     * @var array<string, list<string>>
      */
     private $prefixDirsPsr4 = array();
     /**
-     * @var array[]
-     * @psalm-var array<string, string>
+     * @var list<string>
      */
     private $fallbackDirsPsr4 = array();
 
     // PSR-0
     /**
-     * @var array[]
-     * @psalm-var array<string, array<string, string[]>>
+     * List of PSR-0 prefixes
+     *
+     * Structured as array('F (first letter)' => array('Foo\Bar (full prefix)' => array('path', 'path2')))
+     *
+     * @var array<string, array<string, list<string>>>
      */
     private $prefixesPsr0 = array();
     /**
-     * @var array[]
-     * @psalm-var array<string, string>
+     * @var list<string>
      */
     private $fallbackDirsPsr0 = array();
 
@@ -81,8 +80,7 @@ class ClassLoader
     private $useIncludePath = false;
 
     /**
-     * @var string[]
-     * @psalm-var array<string, string>
+     * @var array<string, string>
      */
     private $classMap = array();
 
@@ -90,21 +88,20 @@ class ClassLoader
     private $classMapAuthoritative = false;
 
     /**
-     * @var bool[]
-     * @psalm-var array<string, bool>
+     * @var array<string, bool>
      */
     private $missingClasses = array();
 
-    /** @var ?string */
+    /** @var string|null */
     private $apcuPrefix;
 
     /**
-     * @var self[]
+     * @var array<string, self>
      */
     private static $registeredLoaders = array();
 
     /**
-     * @param ?string $vendorDir
+     * @param string|null $vendorDir
      */
     public function __construct($vendorDir = null)
     {
@@ -113,7 +110,7 @@ public function __construct($vendorDir = null)
     }
 
     /**
-     * @return string[]
+     * @return array<string, list<string>>
      */
     public function getPrefixes()
     {
@@ -125,8 +122,7 @@ public function getPrefixes()
     }
 
     /**
-     * @return array[]
-     * @psalm-return array<string, array<int, string>>
+     * @return array<string, list<string>>
      */
     public function getPrefixesPsr4()
     {
@@ -134,8 +130,7 @@ public function getPrefixesPsr4()
     }
 
     /**
-     * @return array[]
-     * @psalm-return array<string, string>
+     * @return list<string>
      */
     public function getFallbackDirs()
     {
@@ -143,8 +138,7 @@ public function getFallbackDirs()
     }
 
     /**
-     * @return array[]
-     * @psalm-return array<string, string>
+     * @return list<string>
      */
     public function getFallbackDirsPsr4()
     {
@@ -152,8 +146,7 @@ public function getFallbackDirsPsr4()
     }
 
     /**
-     * @return string[] Array of classname => path
-     * @psalm-return array<string, string>
+     * @return array<string, string> Array of classname => path
      */
     public function getClassMap()
     {
@@ -161,8 +154,7 @@ public function getClassMap()
     }
 
     /**
-     * @param string[] $classMap Class to filename map
-     * @psalm-param array<string, string> $classMap
+     * @param array<string, string> $classMap Class to filename map
      *
      * @return void
      */
@@ -179,24 +171,25 @@ public function addClassMap(array $classMap)
      * Registers a set of PSR-0 directories for a given prefix, either
      * appending or prepending to the ones previously set for this prefix.
      *
-     * @param string          $prefix  The prefix
-     * @param string[]|string $paths   The PSR-0 root directories
-     * @param bool            $prepend Whether to prepend the directories
+     * @param string              $prefix  The prefix
+     * @param list<string>|string $paths   The PSR-0 root directories
+     * @param bool                $prepend Whether to prepend the directories
      *
      * @return void
      */
     public function add($prefix, $paths, $prepend = false)
     {
+        $paths = (array) $paths;
         if (!$prefix) {
             if ($prepend) {
                 $this->fallbackDirsPsr0 = array_merge(
-                    (array) $paths,
+                    $paths,
                     $this->fallbackDirsPsr0
                 );
             } else {
                 $this->fallbackDirsPsr0 = array_merge(
                     $this->fallbackDirsPsr0,
-                    (array) $paths
+                    $paths
                 );
             }
 
@@ -205,19 +198,19 @@ public function add($prefix, $paths, $prepend = false)
 
         $first = $prefix[0];
         if (!isset($this->prefixesPsr0[$first][$prefix])) {
-            $this->prefixesPsr0[$first][$prefix] = (array) $paths;
+            $this->prefixesPsr0[$first][$prefix] = $paths;
 
             return;
         }
         if ($prepend) {
             $this->prefixesPsr0[$first][$prefix] = array_merge(
-                (array) $paths,
+                $paths,
                 $this->prefixesPsr0[$first][$prefix]
             );
         } else {
             $this->prefixesPsr0[$first][$prefix] = array_merge(
                 $this->prefixesPsr0[$first][$prefix],
-                (array) $paths
+                $paths
             );
         }
     }
@@ -226,9 +219,9 @@ public function add($prefix, $paths, $prepend = false)
      * Registers a set of PSR-4 directories for a given namespace, either
      * appending or prepending to the ones previously set for this namespace.
      *
-     * @param string          $prefix  The prefix/namespace, with trailing '\\'
-     * @param string[]|string $paths   The PSR-4 base directories
-     * @param bool            $prepend Whether to prepend the directories
+     * @param string              $prefix  The prefix/namespace, with trailing '\\'
+     * @param list<string>|string $paths   The PSR-4 base directories
+     * @param bool                $prepend Whether to prepend the directories
      *
      * @throws \InvalidArgumentException
      *
@@ -236,17 +229,18 @@ public function add($prefix, $paths, $prepend = false)
      */
     public function addPsr4($prefix, $paths, $prepend = false)
     {
+        $paths = (array) $paths;
         if (!$prefix) {
             // Register directories for the root namespace.
             if ($prepend) {
                 $this->fallbackDirsPsr4 = array_merge(
-                    (array) $paths,
+                    $paths,
                     $this->fallbackDirsPsr4
                 );
             } else {
                 $this->fallbackDirsPsr4 = array_merge(
                     $this->fallbackDirsPsr4,
-                    (array) $paths
+                    $paths
                 );
             }
         } elseif (!isset($this->prefixDirsPsr4[$prefix])) {
@@ -256,18 +250,18 @@ public function addPsr4($prefix, $paths, $prepend = false)
                 throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
             }
             $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
-            $this->prefixDirsPsr4[$prefix] = (array) $paths;
+            $this->prefixDirsPsr4[$prefix] = $paths;
         } elseif ($prepend) {
             // Prepend directories for an already registered namespace.
             $this->prefixDirsPsr4[$prefix] = array_merge(
-                (array) $paths,
+                $paths,
                 $this->prefixDirsPsr4[$prefix]
             );
         } else {
             // Append directories for an already registered namespace.
             $this->prefixDirsPsr4[$prefix] = array_merge(
                 $this->prefixDirsPsr4[$prefix],
-                (array) $paths
+                $paths
             );
         }
     }
@@ -276,8 +270,8 @@ public function addPsr4($prefix, $paths, $prepend = false)
      * Registers a set of PSR-0 directories for a given prefix,
      * replacing any others previously set for this prefix.
      *
-     * @param string          $prefix The prefix
-     * @param string[]|string $paths  The PSR-0 base directories
+     * @param string              $prefix The prefix
+     * @param list<string>|string $paths  The PSR-0 base directories
      *
      * @return void
      */
@@ -294,8 +288,8 @@ public function set($prefix, $paths)
      * Registers a set of PSR-4 directories for a given namespace,
      * replacing any others previously set for this namespace.
      *
-     * @param string          $prefix The prefix/namespace, with trailing '\\'
-     * @param string[]|string $paths  The PSR-4 base directories
+     * @param string              $prefix The prefix/namespace, with trailing '\\'
+     * @param list<string>|string $paths  The PSR-4 base directories
      *
      * @throws \InvalidArgumentException
      *
@@ -481,9 +475,9 @@ public function findFile($class)
     }
 
     /**
-     * Returns the currently registered loaders indexed by their corresponding vendor directories.
+     * Returns the currently registered loaders keyed by their corresponding vendor directories.
      *
-     * @return self[]
+     * @return array<string, self>
      */
     public static function getRegisteredLoaders()
     {
diff --git a/lib/composer/composer/autoload_classmap.php b/lib/composer/composer/autoload_classmap.php
index e53b4fe94c6e0..ba3edcad4f237 100644
--- a/lib/composer/composer/autoload_classmap.php
+++ b/lib/composer/composer/autoload_classmap.php
@@ -431,6 +431,7 @@
     'OCP\\HintException' => $baseDir . '/lib/public/HintException.php',
     'OCP\\Http\\Client\\IClient' => $baseDir . '/lib/public/Http/Client/IClient.php',
     'OCP\\Http\\Client\\IClientService' => $baseDir . '/lib/public/Http/Client/IClientService.php',
+    'OCP\\Http\\Client\\IPromise' => $baseDir . '/lib/public/Http/Client/IPromise.php',
     'OCP\\Http\\Client\\IResponse' => $baseDir . '/lib/public/Http/Client/IResponse.php',
     'OCP\\Http\\Client\\LocalServerException' => $baseDir . '/lib/public/Http/Client/LocalServerException.php',
     'OCP\\Http\\WellKnown\\GenericResponse' => $baseDir . '/lib/public/Http/WellKnown/GenericResponse.php',
@@ -1335,6 +1336,7 @@
     'OC\\Http\\Client\\Client' => $baseDir . '/lib/private/Http/Client/Client.php',
     'OC\\Http\\Client\\ClientService' => $baseDir . '/lib/private/Http/Client/ClientService.php',
     'OC\\Http\\Client\\DnsPinMiddleware' => $baseDir . '/lib/private/Http/Client/DnsPinMiddleware.php',
+    'OC\\Http\\Client\\GuzzlePromiseAdapter' => $baseDir . '/lib/private/Http/Client/GuzzlePromiseAdapter.php',
     'OC\\Http\\Client\\NegativeDnsCache' => $baseDir . '/lib/private/Http/Client/NegativeDnsCache.php',
     'OC\\Http\\Client\\Response' => $baseDir . '/lib/private/Http/Client/Response.php',
     'OC\\Http\\CookieHelper' => $baseDir . '/lib/private/Http/CookieHelper.php',
diff --git a/lib/composer/composer/autoload_static.php b/lib/composer/composer/autoload_static.php
index 58bdace5dcbb6..b28fd124109d1 100644
--- a/lib/composer/composer/autoload_static.php
+++ b/lib/composer/composer/autoload_static.php
@@ -464,6 +464,7 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OCP\\HintException' => __DIR__ . '/../../..' . '/lib/public/HintException.php',
         'OCP\\Http\\Client\\IClient' => __DIR__ . '/../../..' . '/lib/public/Http/Client/IClient.php',
         'OCP\\Http\\Client\\IClientService' => __DIR__ . '/../../..' . '/lib/public/Http/Client/IClientService.php',
+        'OCP\\Http\\Client\\IPromise' => __DIR__ . '/../../..' . '/lib/public/Http/Client/IPromise.php',
         'OCP\\Http\\Client\\IResponse' => __DIR__ . '/../../..' . '/lib/public/Http/Client/IResponse.php',
         'OCP\\Http\\Client\\LocalServerException' => __DIR__ . '/../../..' . '/lib/public/Http/Client/LocalServerException.php',
         'OCP\\Http\\WellKnown\\GenericResponse' => __DIR__ . '/../../..' . '/lib/public/Http/WellKnown/GenericResponse.php',
@@ -1368,6 +1369,7 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OC\\Http\\Client\\Client' => __DIR__ . '/../../..' . '/lib/private/Http/Client/Client.php',
         'OC\\Http\\Client\\ClientService' => __DIR__ . '/../../..' . '/lib/private/Http/Client/ClientService.php',
         'OC\\Http\\Client\\DnsPinMiddleware' => __DIR__ . '/../../..' . '/lib/private/Http/Client/DnsPinMiddleware.php',
+        'OC\\Http\\Client\\GuzzlePromiseAdapter' => __DIR__ . '/../../..' . '/lib/private/Http/Client/GuzzlePromiseAdapter.php',
         'OC\\Http\\Client\\NegativeDnsCache' => __DIR__ . '/../../..' . '/lib/private/Http/Client/NegativeDnsCache.php',
         'OC\\Http\\Client\\Response' => __DIR__ . '/../../..' . '/lib/private/Http/Client/Response.php',
         'OC\\Http\\CookieHelper' => __DIR__ . '/../../..' . '/lib/private/Http/CookieHelper.php',
diff --git a/lib/private/Http/Client/Client.php b/lib/private/Http/Client/Client.php
index 298749d52e161..3bf43e6c07ec6 100644
--- a/lib/private/Http/Client/Client.php
+++ b/lib/private/Http/Client/Client.php
@@ -34,13 +34,16 @@
 namespace OC\Http\Client;
 
 use GuzzleHttp\Client as GuzzleClient;
+use GuzzleHttp\Promise\PromiseInterface;
 use GuzzleHttp\RequestOptions;
 use OCP\Http\Client\IClient;
+use OCP\Http\Client\IPromise;
 use OCP\Http\Client\IResponse;
 use OCP\Http\Client\LocalServerException;
 use OCP\ICertificateManager;
 use OCP\IConfig;
 use OCP\Security\IRemoteHostValidator;
+use Psr\Log\LoggerInterface;
 use function parse_url;
 
 /**
@@ -61,7 +64,8 @@ public function __construct(
 		IConfig $config,
 		ICertificateManager $certificateManager,
 		GuzzleClient $client,
-		IRemoteHostValidator $remoteHostValidator
+		IRemoteHostValidator $remoteHostValidator,
+		protected LoggerInterface $logger,
 	) {
 		$this->config = $config;
 		$this->client = $client;
@@ -205,7 +209,7 @@ protected function preventLocalAddress(string $uri, array $options): void {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -236,7 +240,7 @@ public function get(string $uri, array $options = []): IResponse {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -271,7 +275,7 @@ public function head(string $uri, array $options = []): IResponse {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -312,7 +316,7 @@ public function post(string $uri, array $options = []): IResponse {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -347,7 +351,7 @@ public function put(string $uri, array $options = []): IResponse {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -370,7 +374,7 @@ public function delete(string $uri, array $options = []): IResponse {
 	}
 
 	/**
-	 * Sends a options request
+	 * Sends an OPTIONS request
 	 *
 	 * @param string $uri
 	 * @param array $options Array such as
@@ -382,7 +386,7 @@ public function delete(string $uri, array $options = []): IResponse {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -403,4 +407,215 @@ public function options(string $uri, array $options = []): IResponse {
 		$response = $this->client->request('options', $uri, $this->buildRequestOptions($options));
 		return new Response($response);
 	}
+
+	protected function wrapGuzzlePromise(PromiseInterface $promise): IPromise {
+		return new GuzzlePromiseAdapter(
+			$promise,
+			$this->logger
+		);
+	}
+
+	/**
+	 * Sends an asynchronous GET request
+	 *
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'query' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 *              'timeout' => 5,
+	 * @return IPromise
+	 */
+	public function getAsync(string $uri, array $options = []): IPromise {
+		$this->preventLocalAddress($uri, $options);
+		$response = $this->client->requestAsync('get', $uri, $this->buildRequestOptions($options));
+		return $this->wrapGuzzlePromise($response);
+	}
+
+	/**
+	 * Sends an asynchronous HEAD request
+	 *
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 *              'timeout' => 5,
+	 * @return IPromise
+	 */
+	public function headAsync(string $uri, array $options = []): IPromise {
+		$this->preventLocalAddress($uri, $options);
+		$response = $this->client->requestAsync('head', $uri, $this->buildRequestOptions($options));
+		return $this->wrapGuzzlePromise($response);
+	}
+
+	/**
+	 * Sends an asynchronous POST request
+	 *
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 *              'timeout' => 5,
+	 * @return IPromise
+	 */
+	public function postAsync(string $uri, array $options = []): IPromise {
+		$this->preventLocalAddress($uri, $options);
+
+		if (isset($options['body']) && is_array($options['body'])) {
+			$options['form_params'] = $options['body'];
+			unset($options['body']);
+		}
+
+		return $this->wrapGuzzlePromise($this->client->requestAsync('post', $uri, $this->buildRequestOptions($options)));
+	}
+
+	/**
+	 * Sends an asynchronous PUT request
+	 *
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 *              'timeout' => 5,
+	 * @return IPromise
+	 */
+	public function putAsync(string $uri, array $options = []): IPromise {
+		$this->preventLocalAddress($uri, $options);
+		$response = $this->client->requestAsync('put', $uri, $this->buildRequestOptions($options));
+		return $this->wrapGuzzlePromise($response);
+	}
+
+	/**
+	 * Sends an asynchronous DELETE request
+	 *
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 *              'timeout' => 5,
+	 * @return IPromise
+	 */
+	public function deleteAsync(string $uri, array $options = []): IPromise {
+		$this->preventLocalAddress($uri, $options);
+		$response = $this->client->requestAsync('delete', $uri, $this->buildRequestOptions($options));
+		return $this->wrapGuzzlePromise($response);
+	}
+
+	/**
+	 * Sends an asynchronous OPTIONS request
+	 *
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 *              'timeout' => 5,
+	 * @return IPromise
+	 */
+	public function optionsAsync(string $uri, array $options = []): IPromise {
+		$this->preventLocalAddress($uri, $options);
+		$response = $this->client->requestAsync('options', $uri, $this->buildRequestOptions($options));
+		return $this->wrapGuzzlePromise($response);
+	}
 }
diff --git a/lib/private/Http/Client/ClientService.php b/lib/private/Http/Client/ClientService.php
index d0640680124d0..532aa7f566ab5 100644
--- a/lib/private/Http/Client/ClientService.php
+++ b/lib/private/Http/Client/ClientService.php
@@ -37,6 +37,7 @@
 use OCP\IConfig;
 use OCP\Security\IRemoteHostValidator;
 use Psr\Http\Message\RequestInterface;
+use Psr\Log\LoggerInterface;
 
 /**
  * Class ClientService
@@ -59,6 +60,7 @@ public function __construct(
 		DnsPinMiddleware $dnsPinMiddleware,
 		IRemoteHostValidator $remoteHostValidator,
 		IEventLogger $eventLogger,
+		protected LoggerInterface $logger,
 	) {
 		$this->config = $config;
 		$this->certificateManager = $certificateManager;
@@ -87,6 +89,7 @@ public function newClient(): IClient {
 			$this->certificateManager,
 			$client,
 			$this->remoteHostValidator,
+			$this->logger,
 		);
 	}
 }
diff --git a/lib/private/Http/Client/GuzzlePromiseAdapter.php b/lib/private/Http/Client/GuzzlePromiseAdapter.php
new file mode 100644
index 0000000000000..9d0b89bfd174e
--- /dev/null
+++ b/lib/private/Http/Client/GuzzlePromiseAdapter.php
@@ -0,0 +1,139 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023, Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC\Http\Client;
+
+use Exception;
+use GuzzleHttp\Exception\RequestException;
+use GuzzleHttp\Promise\PromiseInterface;
+use LogicException;
+use OCP\Http\Client\IPromise;
+use OCP\Http\Client\IResponse;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Log\LoggerInterface;
+
+/**
+ * A wrapper around Guzzle's PromiseInterface
+ *
+ * @see \GuzzleHttp\Promise\PromiseInterface
+ * @since 28.0.0
+ */
+class GuzzlePromiseAdapter implements IPromise {
+	public function __construct(
+		protected PromiseInterface $promise,
+		protected LoggerInterface $logger,
+	) {
+	}
+
+	/**
+	 * Appends fulfillment and rejection handlers to the promise, and returns
+	 * a new promise resolving to the return value of the called handler.
+	 *
+	 * @param ?callable(IResponse): void $onFulfilled Invoked when the promise fulfills. Gets an \OCP\Http\Client\IResponse passed in as argument
+	 * @param ?callable(Exception): void $onRejected  Invoked when the promise is rejected. Gets an \Exception passed in as argument
+	 *
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function then(
+		?callable $onFulfilled = null,
+		?callable $onRejected = null,
+	): IPromise {
+		if ($onFulfilled !== null) {
+			$wrappedOnFulfilled = static function (ResponseInterface $response) use ($onFulfilled) {
+				$onFulfilled(new Response($response));
+			};
+		} else {
+			$wrappedOnFulfilled = null;
+		}
+
+		if ($onRejected !== null) {
+			$wrappedOnRejected = static function (RequestException $e) use ($onRejected) {
+				$onRejected($e);
+			};
+		} else {
+			$wrappedOnRejected = null;
+		}
+
+		$this->promise->then($wrappedOnFulfilled, $wrappedOnRejected);
+		return $this;
+	}
+
+	/**
+	 * Get the state of the promise ("pending", "rejected", or "fulfilled").
+	 *
+	 * The three states can be checked against the constants defined:
+	 * STATE_PENDING, STATE_FULFILLED, and STATE_REJECTED.
+	 *
+	 * @return IPromise::STATE_*
+	 * @since 28.0.0
+	 */
+	public function getState(): string {
+		$state = $this->promise->getState();
+		if ($state === PromiseInterface::FULFILLED) {
+			return self::STATE_FULFILLED;
+		}
+		if ($state === PromiseInterface::REJECTED) {
+			return self::STATE_REJECTED;
+		}
+		if ($state === PromiseInterface::PENDING) {
+			return self::STATE_PENDING;
+		}
+
+		$this->logger->error('Unexpected promise state "{state}" returned by Guzzle', [
+			'state' => $state,
+		]);
+		return self::STATE_PENDING;
+	}
+
+	/**
+	 * Cancels the promise if possible.
+	 *
+	 * @link https://github.com/promises-aplus/cancellation-spec/issues/7
+	 * @since 28.0.0
+	 */
+	public function cancel(): void {
+		$this->promise->cancel();
+	}
+
+	/**
+	 * Waits until the promise completes if possible.
+	 *
+	 * Pass $unwrap as true to unwrap the result of the promise, either
+	 * returning the resolved value or throwing the rejected exception.
+	 *
+	 * If the promise cannot be waited on, then the promise will be rejected.
+	 *
+	 * @param bool $unwrap
+	 *
+	 * @return mixed
+	 *
+	 * @throws LogicException if the promise has no wait function or if the
+	 *                         promise does not settle after waiting.
+	 * @since 28.0.0
+	 */
+	public function wait(bool $unwrap = true): mixed {
+		return $this->promise->wait($unwrap);
+	}
+}
diff --git a/lib/public/Http/Client/IClient.php b/lib/public/Http/Client/IClient.php
index d692edc5b71d4..fb1760c25f216 100644
--- a/lib/public/Http/Client/IClient.php
+++ b/lib/public/Http/Client/IClient.php
@@ -44,7 +44,7 @@ interface IClient {
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -69,7 +69,7 @@ public function get(string $uri, array $options = []): IResponse;
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -99,7 +99,7 @@ public function head(string $uri, array $options = []): IResponse;
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -129,7 +129,7 @@ public function post(string $uri, array $options = []): IResponse;
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -159,7 +159,7 @@ public function put(string $uri, array $options = []): IResponse;
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -178,7 +178,7 @@ public function put(string $uri, array $options = []): IResponse;
 	public function delete(string $uri, array $options = []): IResponse;
 
 	/**
-	 * Sends a options request
+	 * Sends an OPTIONS request
 	 * @param string $uri
 	 * @param array $options Array such as
 	 *              'body' => [
@@ -189,7 +189,7 @@ public function delete(string $uri, array $options = []): IResponse;
 	 *              'headers' => [
 	 *                  'foo' => 'bar',
 	 *              ],
-	 *              'cookies' => ['
+	 *              'cookies' => [
 	 *                  'foo' => 'bar',
 	 *              ],
 	 *              'allow_redirects' => [
@@ -206,4 +206,173 @@ public function delete(string $uri, array $options = []): IResponse;
 	 * @since 8.1.0
 	 */
 	public function options(string $uri, array $options = []): IResponse;
+
+	/**
+	 * Sends an asynchronous GET request
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'query' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function getAsync(string $uri, array $options = []): IPromise;
+
+	/**
+	 * Sends an asynchronous HEAD request
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function headAsync(string $uri, array $options = []): IPromise;
+
+	/**
+	 * Sends an asynchronous POST request
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function postAsync(string $uri, array $options = []): IPromise;
+
+	/**
+	 * Sends an asynchronous PUT request
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function putAsync(string $uri, array $options = []): IPromise;
+
+	/**
+	 * Sends an asynchronous DELETE request
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function deleteAsync(string $uri, array $options = []): IPromise;
+
+	/**
+	 * Sends an asynchronous OPTIONS request
+	 * @param string $uri
+	 * @param array $options Array such as
+	 *              'body' => [
+	 *                  'field' => 'abc',
+	 *                  'other_field' => '123',
+	 *                  'file_name' => fopen('/path/to/file', 'r'),
+	 *              ],
+	 *              'headers' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'cookies' => [
+	 *                  'foo' => 'bar',
+	 *              ],
+	 *              'allow_redirects' => [
+	 *                   'max'       => 10,  // allow at most 10 redirects.
+	 *                   'strict'    => true,     // use "strict" RFC compliant redirects.
+	 *                   'referer'   => true,     // add a Referer header
+	 *                   'protocols' => ['https'] // only allow https URLs
+	 *              ],
+	 *              'sink' => '/path/to/file', // save to a file or a stream
+	 *              'verify' => true, // bool or string to CA file
+	 *              'debug' => true,
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function optionsAsync(string $uri, array $options = []): IPromise;
 }
diff --git a/lib/public/Http/Client/IPromise.php b/lib/public/Http/Client/IPromise.php
new file mode 100644
index 0000000000000..29e186d0168b3
--- /dev/null
+++ b/lib/public/Http/Client/IPromise.php
@@ -0,0 +1,100 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023, Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCP\Http\Client;
+
+use Exception;
+use LogicException;
+
+/**
+ * A wrapper around Guzzle's PromiseInterface
+ * @see \GuzzleHttp\Promise\PromiseInterface
+ * @since 28.0.0
+ */
+interface IPromise {
+	/**
+	 * @since 28.0.0
+	 */
+	public const STATE_PENDING = 'pending';
+	/**
+	 * @since 28.0.0
+	 */
+	public const STATE_FULFILLED = 'fulfilled';
+	/**
+	 * @since 28.0.0
+	 */
+	public const STATE_REJECTED = 'rejected';
+
+	/**
+	 * Appends fulfillment and rejection handlers to the promise, and returns
+	 * a new promise resolving to the return value of the called handler.
+	 *
+	 * @param ?callable(IResponse): void $onFulfilled Invoked when the promise fulfills. Gets an \OCP\Http\Client\IResponse passed in as argument
+	 * @param ?callable(Exception): void $onRejected  Invoked when the promise is rejected. Gets an \Exception passed in as argument
+	 *
+	 * @return IPromise
+	 * @since 28.0.0
+	 */
+	public function then(
+		?callable $onFulfilled = null,
+		?callable $onRejected = null,
+	): IPromise;
+
+	/**
+	 * Get the state of the promise ("pending", "rejected", or "fulfilled").
+	 *
+	 * The three states can be checked against the constants defined:
+	 * STATE_PENDING, STATE_FULFILLED, and STATE_REJECTED.
+	 *
+	 * @return self::STATE_*
+	 * @since 28.0.0
+	 */
+	public function getState(): string;
+
+	/**
+	 * Cancels the promise if possible.
+	 *
+	 * @link https://github.com/promises-aplus/cancellation-spec/issues/7
+	 * @since 28.0.0
+	 */
+	public function cancel(): void;
+
+	/**
+	 * Waits until the promise completes if possible.
+	 *
+	 * Pass $unwrap as true to unwrap the result of the promise, either
+	 * returning the resolved value or throwing the rejected exception.
+	 *
+	 * If the promise cannot be waited on, then the promise will be rejected.
+	 *
+	 * @param bool $unwrap
+	 *
+	 * @return mixed
+	 *
+	 * @throws LogicException if the promise has no wait function or if the
+	 *                         promise does not settle after waiting.
+	 * @since 28.0.0
+	 */
+	public function wait(bool $unwrap = true): mixed;
+}
diff --git a/tests/lib/Http/Client/ClientServiceTest.php b/tests/lib/Http/Client/ClientServiceTest.php
index 72281a0453ce0..40da0a2111c77 100644
--- a/tests/lib/Http/Client/ClientServiceTest.php
+++ b/tests/lib/Http/Client/ClientServiceTest.php
@@ -23,6 +23,7 @@
 use OCP\IConfig;
 use OCP\Security\IRemoteHostValidator;
 use Psr\Http\Message\RequestInterface;
+use Psr\Log\LoggerInterface;
 
 /**
  * Class ClientServiceTest
@@ -41,13 +42,15 @@ public function testNewClient(): void {
 			});
 		$remoteHostValidator = $this->createMock(IRemoteHostValidator::class);
 		$eventLogger = $this->createMock(IEventLogger::class);
+		$logger = $this->createMock(LoggerInterface::class);
 
 		$clientService = new ClientService(
 			$config,
 			$certificateManager,
 			$dnsPinMiddleware,
 			$remoteHostValidator,
-			$eventLogger
+			$eventLogger,
+			$logger,
 		);
 
 		$handler = new CurlHandler();
@@ -65,7 +68,8 @@ public function testNewClient(): void {
 				$config,
 				$certificateManager,
 				$guzzleClient,
-				$remoteHostValidator
+				$remoteHostValidator,
+				$logger,
 			),
 			$clientService->newClient()
 		);
diff --git a/tests/lib/Http/Client/ClientTest.php b/tests/lib/Http/Client/ClientTest.php
index 9a4fb1c657e0f..e48e237e0cc7a 100644
--- a/tests/lib/Http/Client/ClientTest.php
+++ b/tests/lib/Http/Client/ClientTest.php
@@ -19,6 +19,7 @@
 use OCP\IConfig;
 use OCP\Security\IRemoteHostValidator;
 use PHPUnit\Framework\MockObject\MockObject;
+use Psr\Log\LoggerInterface;
 use function parse_url;
 
 /**
@@ -44,11 +45,13 @@ protected function setUp(): void {
 		$this->guzzleClient = $this->createMock(\GuzzleHttp\Client::class);
 		$this->certificateManager = $this->createMock(ICertificateManager::class);
 		$this->remoteHostValidator = $this->createMock(IRemoteHostValidator::class);
+		$this->logger = $this->createMock(LoggerInterface::class);
 		$this->client = new Client(
 			$this->config,
 			$this->certificateManager,
 			$this->guzzleClient,
-			$this->remoteHostValidator
+			$this->remoteHostValidator,
+			$this->logger,
 		);
 	}