I would just like to highlight the "excellent" bit here. It is a tour de force, a masterpiece. Beautifully factored software. They've done an excellent job incrementally building trust and delivering. Really cool project, and I'm so glad it exists.

I also did not realize it is… primarily developed by a single person? The author. Incredible:

https://github.com/stalwartlabs/stalwart/graphs/contributors

This should be pretty straightforward to do with an IMAP <-> IMAP syncing tool, like mbsync [1]. You'd run it periodically in the background to sync the remote IMAP to Stalwart's local IMAP server, and Stalwart can then automatically serve that via JMAP, doing the translation internally.

I was originally thinking you'd need to go remote IMAP <-> maildir <-> Stalwart IMAP, which would be really complicated, but I think the IMAP <-> IMAP should work fine.

[1] https://isync.sourceforge.io/mbsync.html

I have been looking for something like this for ages. Everything I found so far is overpriced, so this is great development.

i have also been pondering this for the exact same reason... unfortunately, i don't have much to show for said pondering... yet...

I'm cautiously optimistic that Stalwart is a game-changer. I would normally stick with a simpler platform (like mox) if I wasn't interested in the groupware space. I've previously tried Nextcloud and SoGo and left disappointed, and have more or less been waiting for a project like this to come along.

Nextcloud was such a terrible experience for me (the file sharing/storage was good, but the groupware aspect was incredibly buggy). But knowing that Nextcloud is partnering with Stalwart to hopefully overhaul their stack, Opencloud is developing their JMAP integration, and Mozilla/Thunderbird is using it too (they already have a webmail in development here: https://github.com/thunderbird/stormbox)... we might finally see some exciting development in this space. And now is also a ripe time, as there seems to be a perfect storm of people wanting to get away from Big Tech platforms.

> Stalwart is essentially the first server implementation of JMAP

Just to clarify. Stalwart is the first to have JMAP contacts and calendars. Cyrus has had JMAP mail since the beginning of JMAP.

There are clients. I use one called aerc.

if I recall correctly FastMail uses JMAP already in production. They were one of the co-authors of the RFC behind it as well

Stalwart isn't the first implementation of JMAP.

It's the first implementation of JMAP applied to stuff other than Mail.

I implemented support for JMAP calendars in Pimsync recently.

You can now synchosise any combination of CalDAV, JMAP, and filesystem.

Cyrus was probably the first

> binary protocol

Email was never a binary protocol. Notoriously so, it's why MIME types and MIME encodings get so complicated.

Most of the "old internet" protocols (email, FTP, even HTTP itself) were bootstrapped on top of built-mostly-for-plaintext Telnet. HTTP as the new telnet has a bunch of improvements when it comes to binary data, request/response-based data flows, and some other considerations. HTTP/3 is even inherently a binary protocol, it's lack of "telnet-compatibility" one of the concerns about switching the majority of the web to it.

vCard/vCal/iCard/iCal were also deeply "plaintext formats". JSON is an improvement because it is more structured, even more efficient, than those predecessors. JSON may not look efficient, but it compresses extremely well and can be quite efficient in gzip and Brotli streams.

I feel like "JSON over HTTP" is a subtle improvement over "custom text formats over telnet", even if it doesn't sound like "binary protocol efficiency" at first glance. Especially as HTTP/3 pushes HTTP more efficient and more "binary", and arguably "more fundamental/basic" with HTTP/3 even taking over more roles in the TCP/UDP layer of the internet stack. (Telnet would never try to replace TCP.) HTTP isn't the worst bootstrap layer the internet could use to build new protocols and apps on top of. Sure, it would be neat to see more variety and experiments outside of the HTTP stack, too, but HTTP is too useful at this point not to build a bunch of things on top of it instead of as their own from-scratch protocol.

> I’m wondering if the design space for new protocols should really be constrained to layers on top of HTTP

It shouldn't. For some cases it helps, but other times it doesn't. Sometimes it helps but there would be better ways to do it, making it on a simpler protocol or making an entirely new protocol (which might or might not use TCP; sometimes it is better to use TCP and sometimes not) depending on the specific case.

> Stuff like file sharing or groupware, mail, calendars, and so on—these things could be a lot more efficient and don’t really need the overhead of JSON as the message interchange format, IMHO

I dislike JSON. I think it has many problems, and that DER is a better format.

(There are also the "small web" protocols such as Gemini and Scorpion and Spartan and Titan, which avoids some of the complexity of HTTP; I had considered using DER-over-Scorpion rather than JSON-over-HTTP. It is also possible to use SSH, although SSH does not have virtual hosting.)

How much overhead do you think fetching emails over http takes? Fetching text documents with HTTP seems like the prime usecase for it. And it's the only way you could have something that works in web clients.

I'm struggling to think of any real benefits to not using HTTP other than it would be more interesting.

> Is there really any new-ish binary protocol these days?

HTTP/2 and HTTP/3 are binary protocols. And if you replace the JSON with CBOR, then even the payload becomes binary.

The reason for using HTTP is that the semantics are right. HTTP is a state transfer protocol, and ultimately, that's 90% of what you need for sync.

The other 10% is for subscriptions, updates, with versioning, and patches. You can get these by adding the Braid extensions (see braid.org) which upgrade HTTP from a state transfer to a state synchronization protocol. (I work on Braid.)

> I’m wondering if the design space for new protocols should really be constrained to layers on top of HTTP.

Absolutely yes, IMO. This significantly eases web client development.

People think serializers are easy, when suddenly this makes a whole raft of choices your problem. You can write your own, and now you have two problems; or you can build on top of capnproto or grpc or, if you really want to get retro, ASN.1 and inherit the problems of your serializer framework.

JSON by comparison has simple, obvious limitations that more people are familiar with dealing with.

There's also the tendency to tie your protocol to implementation. The Microsoft Exchange "protocol" didn't get reverse engineered for so long because it's basically the COM structure of Outlook fed through (if I remember rightly) DCOM-RPC.

I wonder if you could transparently upgrade to CBOR over HTTP/2.

My hot take is that if the web had been based on binary protocols rather than HTML and JSON, the fragmentation of tooling that can instead be standardized as view-source and network-tabs would have decimated (as in removed 90% of) the hackers that make up this community, and software engineering in general.

There's no magic. Nothing sacred. Nothing that you aren't allowed to understand, intuitively. Nothing where you aren't allowed to imagine "what if it also had X?" The web is yours. The computer is yours. As an industry, we burn some incremental percentage of bandwidth to give you the keys to the kingdom, and to allow you, new developer, to be one of us.

In an age when LLMs feel like magic boxes to tech-minded people new to development, we need this more than ever.

JMAP is only JSON over HTTP because that's what all the libraries support. Any data format which provides hashes and arrays would work fine, over any transport. So you could use CBOR or protocol buffers or whatever, over any channel you like.

I don’t think JMAP Calendar spec has been ratified yet.

https://datatracker.ietf.org/doc/draft-ietf-jmap-calendars/

And Contacts was only 10-months ago.

https://www.rfc-editor.org/rfc/rfc9610.html

We're working on it. We still use an unholy set of earlier versions of JMAP internally for our contacts and calendars; in particular the caldav_sync code is gnarly - I wrote it over 10 years ago when I knew less about calendars than I do now! It's still using an earlier branch of what became the perl Net::CalDAVTalk library interally, even though our frontend API is an almost-up-to-date version of what will become the JMAP Calendars spec eventually.

The downsides of developing and testing this stuff as we were writing it up!

We've finished rewriting the objectid generation to give smaller sized and more sortable IDs (they're an inverse of nanosecond internaldates now, plus some extra magic on the low bits for IMAP appends to avoid clashes)... which we wanted to speed up and reduce disk usage for the offline mode.

Next up is indeed updating to the latest spec on calendars and contacts. Files might take a bit longer, I really want to do some desktop clients for the files system, we have a really nice files backend at Fastmail which is only accessible via our interface or WebDAV right now.

What good is a protocol like JMAP as long as common clients like Thunderbird, K-9 Mail, the iPhone email client and others don't support it? Without some concerted effort it will never take off. Then there is the question of what problem it solves that isn't already solved by existing solutions.

Solved problem? Dovecot can't handle UTF-8 to this day. Things like Stalwart do try and change that and actually support non-legacy features. (Though I think Stalwart doesn't do IMAP NOTIFY either.)

Clients on the other hand have actually kinda moved forward, Apple Mail works with IMAP servers and offers features that people only got with Gmail before. But there are many other examples as well.

> What is profit to have good server with new good (assume it is good, I'm not sure, but lets assume) protocols without good client?

You need both. You could say, what profit is a good client without a server? By that reasoning, we never stake a step forward without a complete solution.

Now a better mail implementation is just a client away.

Outlook ? Lol. In 2 years-time Outlook will only connect to MS365 and that's it. You're betting MS will switch to JMAP ? Lol again.

P.S. ("New" Outlook already only connects to MS365 servers and then stores your credentials and data on Azure, while they proxy to your actual IMAP/SMTP server )

Serious question: what’s the differentiator if major email providers don’t support it?

(This should not be interpreted as a defense of IMAP.)

JMAP is great for thin clients, like webmail, or clients which can’t store any state to disk.

For regular desktop software, I’m not sure that it’s really an improvement over existing protocols.

We need better server support first.

I’ve got a friend who’s been pitching me on building a new email client for years. “I’ll do it if we exclusively use JMAP.” “okay does that include Gmail and Apple/iCloud accounts?” “Nope.”

I could sort of see dual-supporting Gmail's proprietary API and JMAP, but unless the #2-5 competitors support it… what’s the point? (sorry to put on the pessimism hat)

There isn’t really a great motivating feature or use-case driving client or server adoption.

To be honest, I’m not sure why end-users would want JMAP for e-mail access.

It would be interesting if they do successfully roll out all of these additional RFC proposals providing a cohesive “groupware” protocol covering calendering, contacts, file shares, etc, we see notable server implementations, and interest is enough to drive client support.

That’s a lot of “ifs”.

I'm setting up Stalwart right now, migrating from my current Maddy+Postfix+Dovecot+Rspamd setup. Not exactly my experience.

The documentation is not great - I'd say it's just about barely enough to get an overall idea, but there's no one proper single definitive overview of what options exist, what are their possible values, what are the defaults, and how they relate to each other. Maddy docs, despite looking a bit sloppy, were a lot easier to get through. IMHO Stalwart makes it unnecessarily difficult to write a non-minimal static configuration file, hooking everything up correctly.

To be fair, maybe there is a page like that but I haven't found it, despite trying.

I know the Web UI allows to do the configuration by clicking through the forms, but this approach conflicts with declarative deployment practices. In my case it's giving me nondescript 500 errors in the UI with "Failed to write local configuration" in the logs because the .toml file is read-only.

Yes, are there any decent JMAP web mail client that we can use?

I have asked sooo many times since Stalwart first was introduced, but not got a straight answer. It is just FastMail or Topicbox. I want something like roudcoube or wildduck that can be used over https that I can self-host!

But is there any real benefit over Postfix + Dovecot other than "it's new and written in Rust?" Postfix and Dovecot have been around for decades and respect the Unix philosophy of doing one thing and doing it well.

Of all of their proposals, this is the most interesting part to me.

I researched what it would take to implement a full calendaring server once, and after reading all the RFCs, just backed away slowly from the whole idea and never thought about it again.

Out of curiosity do you front-end SMTP with postfix to have many queues/MX entries and a battle hardened front-end or is Stalwart handling inbound connections directly? Im thinking of moving from Dovecot to Stalwart so family members have more modern features on my fallback domains about half of my domains do not use Fastmail. In multiple companies I had several Postfix inbound servers to keep the internet from touching Exchange directly and have multiple nodes for companies to quickly hand off to in multiple locations.

I second that; only running it for personal use on a few domains, but handles all the complexity _extremely_ easily.

Can you share what's your solution for filtering incoming spam? I've had to abandon Stalwart because its spam filter is so ineffective and inconsistent.

Where is the overhead in a container? It is just a regular process. (Ok plus a container runtime process, but that is negligible)

isn't it a static binary? Can't you do it the old-school sysadmin way and pull down a binary from github releases and update a symbolic link?

What resource constraints allow you to apt-get but not docker pull? It’s the same resulting stack isn’t it?

I am most curious

I have had similarly been unable to get as much help from their Discord as I had hoped.

That said, I'd give this another shot. What I discovered is that Stalwart is incredibly flexible and designed to be used in any configuration you want, and the documentation and examples are incredible, compared to most other projects. BTW, there is no webmail yet, but you are right that there is the admin that is served over HTTP/S, as well as MTA_STS, JMAP. The default listeners get you started and it's kind of out-of-the-scope of Stalwart in terms how you want your server to interact with those listeners. But whether you containerize it or setup a reverse proxy, the documentation has a lot of examples, including how to pick up the certificates, if not managed by Stalwart itself.

I landed on a Caddy for HTTPS and haproxy for proxy protocol on just JMAP, and the remaining TCP services directly binded to the host for the main mail services.

Traefik is another example that I had initially prepped and got working that also handled TCP connections with proxy protocol where needed. The Stalwart documentation was very helpful with that.

In short, I was impressed with how easy it was to integrate Stalwart into whatever setup I wanted, and how open the developer is to different setups. For instance, mox (while awesome in its own right) considers containerized setups to be not-recommended, and generally expects it to live on its own server. Stalwart is flexible, but the side effect is that it is overwhelming at first... but becomes quite elegant once you get the hang of it.

The installation instructions seem to agree with you:

1. curl this shell script

2. Run it as root.

Anytime you see that, you can assume the software wants to take over the whole box and isn't likely to make any attempt to play nicely with other services/software/users already running on the same host.

To their credit, they do have a docker image (https://stalw.art/docs/install/platform/docker).

You're right to ask it

Always relevant: https://xkcd.com/927/

Yeah because everything already supports WebDAV. It works well with iOS and Android which is imo a big advantage.

However, doesn't stalwart already also support WebDAV though?

> I can understand why JMAP instead of IMAP given the latter's antiquated design.

I think we're about ten years past the point where "newer = better" was a reasonable starting presumption.

What AI stuff are you referring to? I just learned about this project from this blog post, so I don't have the full context on their AI work.

Why does the optional (supported only in the enterprise version) feature bother you?

Do you mean the spam detection algorythm or something else?

The big pitch for JMAP is for a modern web-tech-only approach to email/calendar/"groupware" servers. One reason to do that would be to make it easier to also build email/calendar/"groupware" clients entirely out of modern web-tech. Today most "web email clients" are bespoke to specific stacks/email servers. A dream of JMAP is that with the right CORS policy a single web client could interact with multiple JMAP servers, using only fetch/XHR.

The modernization efforts of JMAP are interesting, too. Most of the old protocols are a mess of bespoke plaintext formats full of quirks evolved over decades in a giant mess of different software. Even the stuff that was already web tech like WebDAV and its extensions CalDAV and CardDAV were full of quirks, violated some REST "rules", and originally intended for a different purpose (file shares/FTP replacement). JMAP is much closer to "plain REST" than WebDAV's complex HTTP protocol extensions/changes.

You may only just have heard of them, but the WG goes back to 2017.

https://datatracker.ietf.org/wg/jmap/history/

Bron is the principal of fastmail, who now own pobox. This is a serious activity.

JMAP and friends are very niche, none of the "mainstream" email clients (that ship with most computers/phones) support it. So this feature being available is unlikely to grow the userbase, IMO.

Now JMAP is quite a bit nicer to use than IMAP's API, but IMAP's gravitational field is too strong to be supplanted. IMAP is also becoming somewhat of a niche protocol, as the majority of users use vendor proprietary protocols for accessing their emails on Gmail, Outlook/Hotmail, etc. So why invest the time to add a niche replacement for IMAP when the entire protocol is a second class citizen to mainstream email clients.

If you look it up, you'll see that JMAP is 6 years old now. It's a protocol for doing email (and now other things) over HTTP, without many of the legacy issues from IMAP and SMTP. https://en.wikipedia.org/wiki/JSON_Meta_Application_Protocol / https://jmap.io/index.html

Agreed, also not clear what this or why it matters. This is a new self-hostable email server basically?