Sentry logging in Bolt CMS

First install Sentry using composer

composer require "sentry/sentry"

Then in index.php add the following directly above the call to the run() function

$client = new Raven_Client('YOUR_SENTRY_DSN');
$error_handler = new Raven_ErrorHandler($client);
$app->error(array($error_handler, 'handleException'), 1);

$app->run();