This tutorial demonstrates how to build a two-way customer support system using Symfony Notifier, Twilio's Programmable SMS API, and Slack's API. The system allows customers to send messages via SMS, which are then forwarded to a Slack channel for customer support team members to respond to. The system also enables the customer support team to reply directly to customer messages via SMS. The tutorial covers setting up the necessary infrastructure, including Twilio and Slack accounts, configuring the Symfony Notifier component, handling incoming SMS messages, forwarding them to a Slack channel, and responding to customer messages in the channel. The system provides a powerful abstraction layer over different communication channels, making it easy for developers to integrate with external messaging services while minimizing the effort required to interact with each platform.