@delta@chaos.social cover

Secure decentralized messaging across all major platforms. Instant and reliable via fast chatmail relays, compatible with classic email providers. Features chat-shared mini web apps for fun and collaboration, end-to-end encrypted and with P2P realtime channels. Security-audited multiple times.

This profile is from a federated server and may be incomplete. View on remote instance

@delta@chaos.social avatar delta , to random

We engage with decentralization protocols a lot (many nerds love to) but make no mistake: in the end, the app needs to work and be easy to use. is a cross-platform FOSS offering, with guaranteed security levels, close to user expectations ... major factors in driving adoption!

True, the email system is not necessarily better than ... but please compare with http://chatmail.at which is fast, ephemeral and secure, with delta inherently being a peer-to-peer E2EE messenger :)

@delta@chaos.social avatar delta , to random

It took a while but it's shaping up nicely :) Post-Quantum Cryptography and Reliable Deletion, better known as Forward Secrecy, are going to become available in 2026 in . For more details, including the recent talk recording:

https://autocrypt2.org

@delta@chaos.social avatar delta , to random

A lot of messaging systems try to reinvent the email system but many (signal, matrix, xmpp) took over one key traditional design which we actually dropped while retaining SMTP/IMAP compatibility: server-controlled identities.

With user identities are cryptographic and reside on end user devices only. Servers are only message relays and have no control over identities or chats, only perform fast message routing. See this fosdem talk by one of our lead developers https://mirror.cyberbits.eu/fosdem/2026/ud2218a/3F9VTU-deltachat-chatmail-relays-multi-transport.av1.webm

@delta@chaos.social avatar delta , to random

Abdanan, January 7th 2026. A 40K people city in Iranian mountains where people took over all police and government buildings, as far as we gather. Internet blockades are happening intermittently in various forms. There a massive sense of uncertainty and panic, also from the government side.

We hear of many people succeeding in using and relays, and are trying, to the best of our abilities, to help people set up communications so families and friends can stay safe.

ALT
@delta@chaos.social avatar delta , to random

We are looking for an experienced Android UI developer for https://github.com/deltachat/deltachat-android. Native Java, close to the system, with minimal deps and fluff.

Networking/encryption/persistence is not part of the job as it happens in https://github.com/chatmail/core

Remote collab is fine and the default. We meet in person every few months in the black forest or other occasions/places. We can do 20-30 hours per week contracts with 4-5K EUR pay per month.

Drop us a DM if you are interested.

@delta@chaos.social avatar delta , to random

Don't believe those who loudly claim email can not avoid metadata! They are ignorant of our continuous works on minimizing metadata:

DONE:

  • no phone number other identifying data needed
  • no cleartext "Subject"
  • no cleartext "To"
  • randomized "Date"
  • no IP addresses
  • group/avatar/attachment/etc metadata only contained in encrypted message parts

Upcoming:

  • servers to never see cryptographic ID metadata
  • remove "threading" and auxilliary headers
  • experiment with Sealed Sender
@delta@chaos.social avatar delta , to random

Iran may be on the verge of Internet shutdowns again. If you have friends or family in , now is the time to let them onboard for example with https://tiiiz.ir -- because using in-country servers helps to stay connected. If you need support for setting up a relay in or for Iran, send us a DM and we'll see to connect you with other knowledgeable operators.
با آرزوی فردایی بهتر...

@delta@chaos.social avatar delta , to random

On this day, two years ago, we published the first chatmail relay, https://delta.chat/en/2023-12-13-chatmail along with templates to replicate the setup, without needing any permission. Two weeks ago we thought there are 60 relays when a hacker handed in a 100+ list 😂
A bunch of knowledgeable folks are now maintaining track of health of the evolving global network, and supporting new operators. 💜💥🖤

thx also for all the support here on the fediverse! its been a wild year and is in 13 days to top it off 😅

@delta@chaos.social avatar delta , to random

Your chat profile/identity: a tar file.

Your social web app: a zip file.

https://chatmail.at and https://webxdc.org are spearheading ever new and more fun ways to deny power to servers and platform billionaires.

Unlike classic email servers, relays do not store user identities which solely live on end-user devices.There also is no encrypted value on the server like with Proton Mail or Signal. There are only relays, endless federating networks of relays to onboard safely :)

ALT
@delta@chaos.social avatar delta , to random

A few things apps are doing positively different from apps

  • easiest onboarding ever; not depending on phone numbers or other private data

  • support for multiple chat profiles/identities

  • decentralized servers, not depending on US-based GAFAM etc.

  • migration from one app/platform and to any other

  • easy multi-device support for any chat profile

  • developers have chances to get their PRs merged :)

  • mini-apps support via https://webxdc.org

anything missing?

@delta@chaos.social avatar delta , to random

On the occasion of SimpleX and Session getting cryptocoin-donations/funding ... we won't hide that most delta contributors are pretty skeptical of cryptocoin-circles. Exhibit 1: apps - mini apps that anyone can whip up -- and the declared motto still on the https://webxdc.org web page since inception mid 2022:

No logins, no coins, no platforms ...

and this year, January 23rd, we added "no billionaires" to the growing list of things deserving a "no" :)

https://delta.chat/en/2025-01-23-webxdc-no-billionaires

ALT
@fuat2mb@theres.life avatar fuat2mb , to Delta Chat

Self-hosted Delta Chat?

I've been thinking more about the hurtle of getting friends and family to use federated/self-hosted services. One of the issues to onboarding is people not "getting" the idea of picking an instance. This has led, in part, to "default" instances, like mastadon.social, that grow so large it almost defeates the idea.

I've been thinking that I really wish had a web client. I have had a MUCH more difficult time getting folks to try that out than even SNS. But I was thinking how the heck are you going to pull that off without @delta having to host the overhead for a robust web client and possibly host a gigantic server system that has to grow exponentially to keep everyone's email from all the possible email providers, really defeating the goal of their project.

This morning, I thought of a possible solution to both problems. What if you have a built-in transfer requirement. So you start with a default, say pleb.joinmastodon.org or noob.delta.chat and after a certain time (3 months or something) you have to either transfer to a new instance, including hosting your own client for in browser decryption web access to your encrypted mail chats or your account (in the case of ) or web client access (in the case of Delta Chat) is shut off.

Do you think this could work?

delta_chat@lemmy.zip icon Delta Chat

delta ,
@delta@chaos.social avatar

@fuat2mb delta_chat@lemmy.zip icon Delta Chat it's a neat idea to postpone server choice until later, and onboard with some default.

apps are currently learning to use multiple addresses at once ("multi-transport"), along with cryptographic hardening against evil server operators. The goal is to provide multi-server onboarding by default, and to automate server migrations (although for a while there will be an advanced settings interface where it's manually managed). You'd be onboarding "to the network" :)

@delta@chaos.social avatar delta , to random

Any data that is collected on servers will eventually leak or be abused otherwise.

By design, no one can enumerate profiles which are private and not published on any server. Conversely, relays do not see or collect private data or metadata.

But wait, there is more :)

We are currently evolving end-to-end security protocols and UX to survive an attacker fully taking over a server. The attacker shall not even be able to message users, let alone impersonate anyone.

ALT
@delta@chaos.social avatar delta , to random

While US-east1 is busy fixing a good part of the Internet, parts of Matrix/Element, X etc down, good old decentralized continues unimpeded and without degradation :)

In other news, there is a new community maintained ❤️ desktop install:

pkg install deltachat-desktop

thanks @feld and others!

@delta@chaos.social avatar delta , to random

Denmark and other EU governments still pursue .

They still want to permanently legalize client-side scanning but postponed making it mandatory.

They also want to increase age-verification controls which risk to ruin what little is left of privacy in current digital spaces, taken hostage already by US corps.

Ourselves? We double down on providing the most private, reliable and fun messaging experience, with a growing federating relay network across the globe.

ALT
@delta@chaos.social avatar delta , to random

We were surprised to hear today that Forbes.ru (a subsidiary of the global Forbes brand it seems) recently published an article quoting an expert recommending to use on the backdrop of restrictions of Signal, Whatsapp, Telegram, Discord and Viber in Russian networks.

https://www.forbes.ru/tekhnologii/548966-ne-gasite-vasi-ekrany-cem-zamenit-telegram-i-whatsapp

@delta@chaos.social avatar delta , to random

We hereby challenge all other messaging apps, FOSS or not, to provide a more convenient private onboarding experience than

  1. Install app
  2. "Create new profile"
  3. Enter nick name, tap "Agree and continue"
  4. Tap "+" and "new contact" and provide/scan qr code/link

Voila! A secure private chat, familiar to those coming from Whatsapp or Telegram (without "AI", with ).

Note: chat identities are private and can not be queried or discovered. Servers keep no track or metadata

Create profile screen With a field to enter a name ... "Fediverse chicken" was typed A link to the privacy policy of nine.testrun.org, the default onboarding chatmail relay A highlighted button "agree and continue" A button "use other server"
Screenshot of newly created profile Title bar "fediverse chicken" Two chats in the chat list: "Device messages" with instructions how to setup contact with another chat profile "Saved messages" where you can "save" messages from other chats to memorize them

ALT
delta OP ,
@delta@chaos.social avatar

@crazy_pony

  1. there are bridges ("matterdelta") which provide interop with Matrix, XMPP, Telegrram, ssh and anything that Matterbridge provides. It doesn't preserve end-to-end encryption and so bridging bot choice is tricky.

  2. There are growing efforts around 3rd party clients https://chatmail.at/clients. Interoperability is "free" between all chatmail clients ( being the prominent one). Unlike we welcome third parties to the party :)

@delta@chaos.social avatar delta , to random

Countering toxicity and fake takes is not just a technical question (moderation, admins etc) but one of social curation both collectively and privately: which people and groups do you/we trust for what. No tool can automate that.

is for private e2ee messaging and mutually curated group chats, and not random social media propelled onboarding. We are with here and not with and who offer public anonymous discovery of large chat groups with lots of unknown folks.

@delta@chaos.social avatar delta , to random

It's done! is officially off the table after the danish EU council presidency drops it for good. It's a small but important victory!

Thanks again to @chatcontrol for coordinating grassroots interventions, and everyone else, especially on the fediverse, for joining efforts to fundamentally preserve end-to-end encryption 💜 Also to @Mer__edith and @signalapp for their strong end-to-end encryption work and stances.

Of course, vigilance remains important.

https://www.euractiv.com/news/danish-presidency-backs-away-from-chat-control/

@delta@chaos.social avatar delta , to random

Signal's president claimed it takes billions to replicate the availability and reliability of "hyperscalers" (AWS/Google/Microsoft/Cloudfare) that Signal uses.

and are about disproving this claim by

  1. making relays super cheap (DONE)

  2. enabling chat profiles to use multiple relays redundantly (WIP)

  3. distributing relay knowledge among chatters (TBD).

Fat servers, corporate overlords and billionaires: not needed and better to not exist for a convivial e2ee future :)

@delta@chaos.social avatar delta , to random

Our project is one of constant exit planning and circumvention considerations ... as times and tech are getting more shitty.

We don't bet on a single basket, and not a single state or jurisdiction, and certainly not AWS/Google/Microsoft US clouds which run servers.

No single hoster, platform or language (we do a lot of Rust, granted) and no single device or vendor. At protocol levels we regard nothing as holy, and look for simplicity and robustness, and convivial community 🖤

ALT
@delta@chaos.social avatar delta , to random

Good news! It's getting harder to keep track of new relays :)

Recently several public relays were added to the https://chatmail.at/relays list, in Warsaw, Helsinki, Romania and Barcelona.🧡

If you have installed on mobile, you can go to any chatmail relay website in the list and click on a link there to create a chat profile.

It's wonderful to hear about collectives setting up chat infrastructure like the recent https://xat.fedi.cat from @fedicat and @eXOfasia

@delta@chaos.social avatar delta , to random

Not taking Venture Capital money means:

  • No pressure to maximize monetization of usage (for every million of VC funding you need to find ~100+ Million in value later).

  • No prioritization of growing fast with PR campaigns that promise the moon and stumble on the ground

  • No billionaire who ultimately profits

Instead, we seek public funding and private contributions for and developments.

Thanks to everyone who is helping and already test-driving things :)

ALT
@delta@chaos.social avatar delta , to random

There is no single central server. Signal uses cloud, plus Google Cloud, Microsoft Cloud and Cloudflare, all under US legislation. If any of these clouds goes down or becomes otherwise problematic, chatting degrades or fails.

With you can choose relays ( https://chatmail.at/relays ) which distributes the risk across a wider network. We are currently working on the multi-transport feature to finally remove any central point of chat failure https://chaos.social/@delta/115362144863345662

delta ,
@delta@chaos.social avatar

@stormii@darmstadt.social avatar stormii @gedaliyah@lemmy.world avatar gedaliyah stay tuned :) directly integrated calls are in development currently, next releases are to come with experimental support.

@delta@chaos.social avatar delta , to random

Forget warn apps and mobiles: when it comes to neighborhoods there are many non-digital ways to help each other. Without needing permission from billionaires.

Whistles!

https://blockclubchicago.org/2025/09/17/in-little-village-residents-are-blowing-actual-whistles-to-warn-neighbors-about-ice/

@signalapp@mastodon.world avatar signalapp , to random

We are alarmed by reports that Germany is on the verge of a catastrophic about-face, reversing its longstanding and principled opposition to the EU’s Chat Control proposal which, if passed, could spell the end of the right to privacy in Europe. https://signal.org/blog/pdfs/germany-chat-control.pdf

delta ,
@delta@chaos.social avatar

@randy_ @gaufff @signalapp the precise legal repercussions and steps how some chat control could be implemented, are guess work. It's a technical quagmire even if players collaborate which we are pretty sure signal and delta chat will not, and rather pull out if it comes to it. At the current moment it's about preventing chatcontrol wholesale because it is an exceptionally bad idea that does not help to protect children or get them out of abuse situations.

@delta@chaos.social avatar delta , to random

While classic cleartext email providers, also Thunderbird with its Thundermail efforts, are aiming to be a more trustworthy alternative to Gmail/calendar/drive etc ...

and efforts go all-in on end-to-end encryption and metadata minimization, with decentralized transport relays playing much lesser roles than 's Amazon/Microsoft/Google servers. At the same time, apps provide unprecedented extensibility, eg checkout the great TOTP app https://webxdc.org/apps/#rtn-totp

@delta@chaos.social avatar delta , to random

While poses an existential threat to the Freiburg merlinux GmbH and distributing apps from within the EU to all stores worldwide, it would resist any chatcontrol legislation up to the German constitutional and EuGH courts.

If the EU based company would need to fold in a few years, there would likely be forks distributed outside the EU that will seamlessly continue to function. Our architecture and FOSS licensing makes sure of it. See also https://chaos.social/@delta/113417740762852318

delta OP ,
@delta@chaos.social avatar

@matiu_bidule Googles planned restrictions on users abilities to install software is horrible. But it doesn't have much to do with the app distribution, as the gmbh is already registered across many stores. We would like to see non-android/non-apple mobile efforts to florish. But let's not mix it too much with the issue of even if it's true that enforcing chatcontrol would likely imply enforcing app distribution via google/apple eventually, and canceling e2ee apps.

@ivantodorov@mastodon.social avatar ivantodorov , to random

Really really happy with Proxmox! Just setting and migrating all of my services atm, report coming as soon as I'm done 😊 But yeah, seems like the most difficult choice right now is which messenger server to self host 😅

delta ,
@delta@chaos.social avatar

@ivantodorov while there is an ongoing effort to dockerize relays, a proxmox version of https://github.com/chatmail/relay/ would be very useful as well. Those relay nodes operate as a cheap chat-optimized federated email server, usable by any app

@delta@chaos.social avatar delta , to random

is a giant legal-technical quagmire and would erode privacy in times where we most need it. But let's talk about protecting children ... what chatcontrol claims to be about:

First, it's unproven that chatcontrol would help lower actual abuses.

Second, why not spend the many EU millions that go into busying politicians, developers, lawyers and orgs into hiring social workers? They could directly act on the huge backlog of reported known child abuse cases. That definitely helps.

@delta@chaos.social avatar delta , to random

The problem with is deep and extremely significant. It would be a paradigm shift that implies state and corporate control of app developers and users, i.e. what you can install on "your" devices. It would empower Google, Apple and Microsoft to increase enclosure even more.

Just as with the p2p wealth of good tools two decades ago, e2e tooling would remain available only to small specialist circles.

Given authoritarian threats everywhere, is an exceptionally bad idea.

@delta@chaos.social avatar delta , to random

What if a state tries to mandate us as app devs/distributors to shut down a chat profile?

Nothing. It can't be done.

We have no list of chat identities, have no handle or data about them, and don't mediate the message transfer.

However, EU politicians and Russian authorities would want us to insert backdoors into our FOSS code. But that is nothing than can happen overnight, and we are fine with friendly forks already. Resilient private internet communication ftw :)

@delta@chaos.social avatar delta , to random

As with the demise of windows10, various meta happenings around Whatsapp open possibilities to welcome refugees. Instead of blaming them for not having had whatever insights earlier, there are often just very practical questions where a helping hand does wonders. Offering help instead of trying to convince.

Currently many companies are giving win11-incompatible laptops away, often powerful systems that deserve upgrading to Linux, and then donating then. It also helps to counter hardware waste.

@delta@chaos.social avatar delta , to random

We are impressed with the new https://fightchatcontrol.eu/ website, and the way it provides all the info needed to engage in distributed diverse action to prevent the EU from preparing the ground for, or sliding into, authoritarianism by breaking end-to-end encryption for everyone. Germany and France are particularly important to engage with and we'll see what we can do from our circles. We don't know the people behind @chatcontrol but big kudos!

@delta@chaos.social avatar delta , to random

V2 is rolling out after weeks of internal testing, a major milestone revising how end-to-end encryption works and bringing more beautiful contact and group profiles, direct access to chat-shared apps in the title bar and a "new email" action with setting a subject for those using a classic server.

Best of all, users and developers don't need to co-ordinate anything for upgrading to V2 despite the massive security rework behind the scenes :)

https://delta.chat/en/2025-08-04-encryption-v2

@delta@chaos.social avatar delta , to random

Some people in successfully use delta with national email providers when outside Internet is cut.

designs are using delay tolerant protocols. Messages are queued when a path is blocked. email servers are made for this and run at planetary scale.
Messages crossing the border may arrive three days later but they arrive.

Peoples can stay in private touch across time and space, to the extent possible in current breakdown times. Which is what delta is about.

@delta@chaos.social avatar delta , to random

Desktop can now run on and Safari, entirely avoiding and Chromium! It's an intended side-effect of the "porting Desktop to " effort led by @treefit which aims to provide a non-Electron packaged version of the Desktop. Here is a video and deep dive into what's working on regular browsers now, and what's missing for a full Web version: https://delta.chat/en/2025-05-22-browser-edition

@delta@chaos.social avatar delta , to random

One thing radically different in compared to Whatsapp and Signal: pervasive, effortless multi-profile support. We understand many worry about how to find others to get in contact with. The dreaded messenger network-scaling problem!

But if you onboard as a group that's less of a worry. We aim to ease and further optimize group-onboarding btw. And sooner or later you'll enjoy multi profile. Creating a chat profile without being chained to a phone number. Freedom and resilience.

@delta@chaos.social avatar delta , to random

We have several ground breaking developments going on in the background, and frankly, it's sometimes hard to not pre-announce them excitedly :)

However, we struggle to acquire public funding after the OTF contract broke away in February. Current need is around ~50K per month for ~10 people. , and we would like to support some contributors to switch their day job.

Fallback: even if funding dries up, is bound to continue to work. It's pretty maintainable and intrinsically motivated.

@delta@chaos.social avatar delta , to random

Today we are unveiling two brand new features by ... drum-roll ... doing nothing:

  • No "AI" integration involved or planned. Consequently, you don't need to teach your relatives how to disable AI!

  • No proprietary server components: servers are fast, efficient and freely replicable, no permissions needed!

Moreover, our apps are easier to use and onboard with than SIM/phone number based apps: Multi-device and Multi-profile handling is a piece of cake.

@SrRochardBunson@universeodon.com avatar SrRochardBunson , to redstateinsurgents group

Have I told you the good news of Delta Chat?

I use & like it a lot. I've played around with & it's got some killer features that Signal doesn't. This is coming from a non-techie, but it uses encypted email in the background & nothing is stored on anyone's server in any country.

That's all awesome, but even more than that it's FUN! Itallows you to do things like play games in the chat with people making FOSS apps for it, I guess.

@feld can probably answer any tech questions, but I wanted to give it a shoutout.

https://friedcheese.us/objects/8dc022a1-438c-41f7-986a-f8e752a3e7c8

redstateinsurgents@a.gup.pe icon redstateinsurgents group

ALT
delta ,
@delta@chaos.social avatar

@david_chisnall @SrRochardBunson @feld redstateinsurgents@a.gup.pe icon redstateinsurgents group
It's true that recipient addresses are today known to the sending SMTP server even if they don't appear in the MIME-message. Recipients' SMTP servers will only see the recipient addresses on their domain, however, and not the recipients of other servers. There are ways to hide both the sender and receiver addresses but that is not implemented yet. As to IP addresses of group members, they are also known to Signal, cloudflare etc.

@delta@chaos.social avatar delta , to random

To clarify a bit what we tried to express earlier today: we came to the Fediverse long before it was cool (musk bought Twitter wave) and we are staying on while it's currently not as cool as Bluesky. We are only doing social media via the fediverse. We are in for the long game, and in our view, this means increasing diversity and collaborative development practises and relations with a wide range of people, projects and researchers, with a shared interest in evading enshittificatiom forces.

@delta@chaos.social avatar delta , to random

Hum, are we the only cross-platform messenger project present in 15+ app stores that primarily announces on, and interacts with, the Fediverse while others use X and maybe Bluesky? If you know of others please mention them in the replies :)

In any case, we are pretty happy here, as we are finding meaningful interactions, and organically evolving interest and collaboration with other people and projects. Probably it helps that shares several traits with protocols? Cheers.

delta OP ,
@delta@chaos.social avatar

@matrix @andybalaam hello matrix :) are you using some special software to crosspost to Twitter and other feeds and then interact with?

@delta@chaos.social avatar delta , to random

Delta Chat is an in-between project: often ignored as a messenger by e-mail companies/experts and then ignored by messenger companies/experts because of its use and interoperability with e-mail. As Heinz von Foerster once said: "If you are doing something genuinely new then don't ask the experts. If you do something that has already been done, then, by all means, ask the experts." FWIW many experts have verified Delta Chat's security mechanics https://delta.chat/en/help#security-audits :)