This public service stores information about Cryptomessaging personas and makes that information publicly available to other apps and Internet services.
There can be many persona services hosted by different individuals, companies, and organizations. A cryptomessaging user can choose any number of persona services to publish their information, and any number of persona services to search for information about others - It's an open market.
This persona service is backed by S3 on AWS to provide highly reliable, available, and scalable storage in a cost effective manner. A persona service can also be backed by blockchain for a different set of trade-offs.
The source code for this service is available at https://github.com/cryptomessaging/persona-service