Understand that JMAP is an object synchronisation protocol. It’s most interested in the problems that are out of scope for GraphQL.

You could have a variant of JMAP with GraphQL syntax and semantics, but there would be a fair bit of mismatch, for their purposes and focuses are quite different: JMAP is concerned with object identity and synchronisation, for what you might call thick clients (and JMAP Mail needs to be broadly IMAP compatible), while GraphQL is UI-focused, for what might reasonably be considered to be thin clients (not that they are logicless, but that they are very much focused on offloading burden to the server). I see no compelling case for a JMAP-like GraphQL thing.

It could still be an interesting task to develop a object synchronisation protocol like the JMAP core on top of GraphQL.

Reading through the JMAP website [0], I'm actually wondering whether whoever's behind JMAP has looked at GraphQL. There seem to be a lot of similarities (especially the "why not REST" section).

[0] https://jmap.io/index.html

Work on JMAP likely started before GraphQL was publicly released.

I think Fastmail are the primary ones behind JMAP: https://fastmail.blog/2014/12/23/jmap-a-better-way-to-email/

Yep. Also I think they are using it for a subset of customers. While JMAP support in Cypht is still new, so far it's working just like IMAP, but my testing is limited since I just wrote the integration :)

Actually, Outlook GraphQL reusing the idea of batch JMAP calls. https://docs.microsoft.com/en-us/previous-versions/office/of...