Getting Started in PHP¶ Add Sqreen to your PHP application to automatically monitor and protect from security issues in production The Sqreen PHP agent monitors your application against attacks, blocks them, and help you identify and solve security issues. The following sections below will help you get started with The Sqreen PHP Agent. The structure of the PHP agent¶ The PHP agent comprises two parts: A daemon, and a language extension. Both are necessary, and they work closely together to secure your PHP web applications. The language extension is the part performing the PHP code instrumentation. It is a compiled extension (just as the MySQL or ODBC extensions) using the PHP engine's API in order to be able to inspect the internal state of PHP, which is necessary to detect and block attacks. The daemon provides a long-running background process where the agent can batch upload reports, watch for new rules to download, and generally perform asynchronous activities that we don't want to impact your PHP application's performance. This is necessary because of the fundamentally transactional nature of PHP applications: Once a request has been serviced, the runtime is destroyed and there is no further chance for us to perform background or synchronous actions.