For the record it seems this seems to do some basic processing:
> The Inbox or Sent folder triggers another Lambda function that loads the raw email, converts it to a .html and .txt file, and stores it alongside the original message, while storing any attachments in the attachments.
This looks OK for me having clients do indexing and processing. From your description it seems JMAP choose a different tradeoffs and puts more services on the server side.
This project seems to be designed more for a process-and-delete workflow, whereas JMAP is designed as a general-purpose object synchronisation protocol on which you can build arbitrary email clients.
For the record it seems this seems to do some basic processing:
> The Inbox or Sent folder triggers another Lambda function that loads the raw email, converts it to a .html and .txt file, and stores it alongside the original message, while storing any attachments in the attachments.
This looks OK for me having clients do indexing and processing. From your description it seems JMAP choose a different tradeoffs and puts more services on the server side.