We live in an exciting time for software where thousands of vendors make competitive tools tailored for a variety of unique business needs. These tools help us do our jobs, but often come at a price; they don't always play nice with each other. Slack is a team-communication tool that acts as a workspace for discussion and collaboration. The Slack platform connects the tools and software you use into this collaborative workspace. As a developer, building software on Slack's platform and listing it on our App Directory present an opportunity for your company to join Slack's mission to make the work lives of your customers simpler, more pleasant, and more productive. I'll give you an overview of the variety of APIs and developer building blocks the Slack Platform provides to help you integrate your products directly with Slack. Building blocks like incoming webhooks, slash commands, events, and bot users allow developers to create applications that range from simple notifications to complex conversational AI. In this talk we'll use a medley of real-world app examples, walk through an introduction to building applications using Slack's APIs, and get our feet wet with a live-coding demonstration of an in-Slack notification of an external service using an incoming webhook.