Zencoder provides HLS output that Fastly can cache and deliver. To start, you'll need to create a Zencoder job that outputs live HLS to S3. Zencoder provides documentation on this setup process.
Next, configure a new Fastly service using the S3 bucket that you are using with Zencoder as an origin. You can refer to our documentation on setting up S3 as an origin.
Once this is complete, you can serve your HLS streams through Fastly as you would any other content.