Slack has become ubiquitous across the tech industry as the de facto platform for company communication and collaboration. Though fundamentally a chat application, Slack itself is also a development platform. In this tutorial, you will learn how to build Slack apps using PHP step-by-step. Slack apps can be created to improve collaboration and workflows at your company or to sell to others. Whether you want to build a chatbot, an interactive set of forms, or something simple to make your workday more efficient, you can leverage the PHP skills you already have, plus some open source software, to build Slack apps quickly.