diff --git a/common/framework/Push.php b/common/framework/Push.php
index e7b22d2e5..4a5a15fda 100644
--- a/common/framework/Push.php
+++ b/common/framework/Push.php
@@ -288,7 +288,7 @@ class Push
 	 */
 	public function setAndroidChannelId(string $android_channel_id): bool
 	{
-		$this->metadata['android_channel_id'] = utf8_trim(utf8_clean($android_channel_id));
+		$this->metadata['channel_id'] = utf8_trim(utf8_clean($android_channel_id));
 		return true;
 	}
 
@@ -374,10 +374,11 @@ class Push
 			$tokens = $this->_getDeviceTokens();
 			$output = null;
 
-			// Android FCM
+			// FCM HTTP v1 or Legacy API
 			if(count($tokens->fcm))
 			{
-				$fcm_driver = $this->getDriver('fcm');
+				$fcm_driver_name = array_key_exists('fcmv1', config('push.types') ?: []) ? 'fcmv1' : 'fcm';
+				$fcm_driver = $this->getDriver($fcm_driver_name);
 				$output = $fcm_driver->send($this, $tokens->fcm);
 				$this->sent += count($output->success);
 				$this->success_tokens = $output ? $output->success : [];
diff --git a/common/framework/drivers/push/fcmv1.php b/common/framework/drivers/push/fcmv1.php
index a8244eb8d..316dd702f 100644
--- a/common/framework/drivers/push/fcmv1.php
+++ b/common/framework/drivers/push/fcmv1.php
@@ -4,13 +4,27 @@ namespace Rhymix\Framework\Drivers\Push;
 
 use Rhymix\Framework\HTTP;
 use Rhymix\Framework\Push;
+use Rhymix\Framework\Storage;
 use Rhymix\Framework\Drivers\PushInterface;
+use Rhymix\Framework\Helpers\CacheItemPoolHelper;
+use Google\Auth\CredentialsLoader;
+use Google\Auth\FetchAuthTokenCache;
+use Google\Auth\Middleware\AuthTokenMiddleware;
+use GuzzleHttp\HandlerStack;
 
 /**
  * The FCM HTTP v1 API Push driver.
  */
 class FCMv1 extends Base implements PushInterface
 {
+	/**
+	 * Default settings.
+	 */
+	const API_URL = 'https://fcm.googleapis.com/v1/projects/%s/messages:send';
+	const BASE_URL = 'https://www.googleapis.com';
+	const SCOPES = ['https://www.googleapis.com/auth/firebase.messaging'];
+	const CHUNK_SIZE = 10;
+
 	/**
 	 * Config keys used by this driver are stored here.
 	 */
@@ -50,6 +64,130 @@ class FCMv1 extends Base implements PushInterface
 	 */
 	public function send(Push $message, array $tokens): \stdClass
 	{
-		return new \stdClass;
+		$output = new \stdClass;
+		$output->success = [];
+		$output->invalid = [];
+		$output->needUpdate = [];
+
+		// Configure Google OAuth2 access token, with appropriate caching.
+		$service_account = Storage::read($this->_config['service_account'] ?? '');
+		$service_account = json_decode($service_account);
+		if (!$service_account || empty($service_account['project_id']))
+		{
+			$message->addError('FCM error: service account JSON file cannot be decoded');
+			return $output;
+		}
+		$creds = CredentialsLoader::makeCredentials(self::SCOPES, $service_account);
+		$cache_helper = new CacheItemPoolHelper(true);
+		$cache_creds = new FetchAuthTokenCache($creds, [], $cache_helper);
+
+		// Configure Guzzle middleware.
+		$middleware = new AuthTokenMiddleware($cache_creds);
+		$stack = HandlerStack::create();
+		$stack->push($middleware);
+
+		// Compose common parts of the payload, leaving the token empty.
+		$api_url = sprintf(self::API_URL, $service_account['project_id']);
+		$payload = ['message' => []];
+		$title = $message->getSubject();
+		$body = $message->getContent();
+		if ($title !== '')
+		{
+			$payload['message']['notification']['title'] = $title;
+		}
+		if ($body !== '')
+		{
+			$payload['message']['notification']['body'] = $body;
+		}
+
+		$metadata = $message->getMetadata();
+		if (count($metadata))
+		{
+			$metadata['sound'] = isset($metadata['sound']) ? $metadata['sound'] : 'default';
+			$payload['message']['android'] = $metadata;
+			$payload['message']['webpush'] = $metadata;
+			$payload['message']['apns']['payload'] = [
+				'aps' => [
+					'alert' => ['title' => $title, 'body' => $body],
+					'sound' => $metadata['sound'],
+					'badge' => $metadata['badge'] ?? '',
+					'category' => $metadata['click_action'] ?? '',
+				],
+			];
+		}
+
+		$data = $message->getData();
+		if (count($data))
+		{
+			$payload['message']['data'] = $data;
+		}
+
+		// Send a notification to each token, grouped into chunks to speed up the process.
+		$chunked_tokens = array_chunk($tokens, self::CHUNK_SIZE);
+		foreach($chunked_tokens as $tokens)
+		{
+			$requests = [];
+			foreach ($tokens as $i => $token)
+			{
+				$requests[$i] = [
+					'url' => $api_url,
+					'method' => 'POST',
+					'data' => null,
+					'headers' => [],
+					'cookies' => [],
+					'settings' => [
+						'auth' => 'google_auth',
+						'base_uri' => self::BASE_URL,
+						'handler' => $stack,
+						'json' => $payload,
+					],
+				];
+				$requests[$i]['settings']['json']['message']['token'] = $token;
+			}
+
+			$responses = HTTP::multiple($requests);
+
+			// TODO: response parsing
+			foreach ($responses as $response)
+			{
+				if ($response->getStatusCode() === 200)
+				{
+					$decoded_response = json_decode($response->getBody());
+					var_dump($response->getStatusCode(), $decoded_response);
+
+					if (!$decoded_response)
+					{
+						$message->addError('FCM error: Invalid Response: '. $response);
+						return $output;
+					}
+					$results = $decoded_response->results ?: [];
+					foreach ($results as $result)
+					{
+						if ($result->error)
+						{
+							$message->addError('FCM error: '. $result->error);
+							$output->invalid[$token] = $token;
+						}
+						elseif ($result->message_id && $result->registration_id)
+						{
+							$output->needUpdate[$token] = $result->registration_id;
+						}
+						else
+						{
+							$output->success[$token] = $result->message_id;
+						}
+					}
+				}
+				else
+				{
+					$decoded_response = json_decode($response->getBody());
+					var_dump($response->getStatusCode(), $decoded_response);
+
+					$message->addError('FCM error: HTTP ' . $response->getStatusCode() . ' ' . $response->getReasonPhrase());
+				}
+			}
+		}
+
+		return $output;
 	}
 }