If you have an existing codebase calling Segment's identify() and track() methods, then you won't have to call Highlight's. Highlight will automatically forward data sent to Segment to your Highlight sessions.
We are currently working with Segment on an official integration where you can enable, configure, and send data to Highlight. If you'd like to use this, then upvote this feature request.
Segment's identify() calls will now start forwarding to Highlight.
To forward analytics.track() calls to Highlight, you will need to use the HighlightSegmentMiddleware. This is available in the highlight.run package starting in version 2.10.0.