Getting Started with SWML: Building Smarter Call Flows in SignalWire

Welcome to a new era of low-code communications. In this SignalWire in Seconds episode, Nicholas introduces SWML (SignalWire Markup Language), a flexible and modern markup language built to streamline the way you create and manage call flows.

SWML builds on the best parts of legacy systems like XML, but adds modern simplicity and power thanks to its tight integration with SignalWire's FreeSWITCH-based infrastructure. It supports both YAML and JSON, giving developers the freedom to work in the format they prefer.

Here’s what you’ll learn in the video:

• How to configure a SignalWire number to run a SWML script

• Writing a simple script using the play, prompt, switch, and record methods

• Routing logic with branches: transfer to sales or voicemail based on user input

• Creating call flows that respond to both voice and keypress input

• How call context and global variables make your logic clean and scalable

Unlike traditional XML-based telephony scripting, SWML allows you to define entire call flows within a single document, including prompts, call transfers, recordings, and logic branches. You’ll even see how to pass through caller ID and handle default behaviors if the caller doesn’t follow instructions.

With just a few lines of SWML, you can build interactive voice apps that feel responsive, modern, and tailored—without having to manage heavy infrastructure or complex boilerplate code.