Mautic is an open-source marketing automation platform built on Symfony (PHP). It provides a comprehensive suite for managing contacts (leads), creating and executing marketing campaigns, sending emails, building forms and landing pages, tracking user interactions, and integrating with third-party CRMs and services. The architecture is a modular monolith with bundles and plugins, a REST API, and a CLI console. Key data flows include contact tracking via tracking pixels and form submissions, campaign execution with scheduled events, email sending with bounce/feedback processing, and integration sync with external systems. External dependencies include MySQL/MariaDB, optional Redis/Memcached caching, a mailer transport, and various third-party APIs for IP geolocation, data enrichment, and social media. The codebase is actively maintained with extensive test coverage, modern PHP practices, and a plugin ecosystem.