AWS S3 History export file type

Greetings,

I wanted to find out if I can get confirmation on the export type?
I am assessing whether the Cloud is a viable option and due to the 90 limitation on data retention I am looking to use the export functionality to an S3 bucket and just wanted to know what type the export is in?

Many thanks,

Event histories are exported in proto format, proto schema here.

More info in docs here if it helps.

Sample to deserialize export type with Temporal Go SDK here.