I want to include the cache purge as part of my release process for integration, but I wasn't able to find anything. Wasn't sure if that was possible.
Assuming you mean the CloudFlare CDN cache, at present it looks like that can only be cleared through the PaaS portal. It's been discussed for a while and there is a feature request to add support for clearing the CDN cache via the deployment API which is flagged as "Planned" but ultimately that feature's not available yet.
The feature request is here:https://feedback.optimizely.com/ideas/DXCS-I-251
Feel free to give it a vote. Maybe that will help to prioritise it.