Notices by Delta Chat (delta@chaos.social)

V2 #deltachat 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

some new #webxdc apps ....for personal or group journaling or "pixel it" for running a minimal original "twitter" style social network in a larger chat group, end-to-end encrypted and private, without anyone outside being able to access anything except for the chat group members. It's the wild-wild-west out there in doing "first apps" for something, and cutting hosting/dns/billionaires-in-the-middle out. See also our blog post earlier this year:
https://delta.chat/en/2025-01-23-webxdc-no-billionaires

We used to look closely at #whatsapp Usability/UX. Not anymore.

Meta is enshittifying WA to become a social media app, charging companies for access to followers, showing ads, and pushing AI slop down the throat of billions of people.

#deltachat remains all about pleasing private messaging UX. Resilient, secure and decentralized. Its trivial to get started as a family, group or little org. Its trivial to migrate between android, iphone, desktop, Ubuntu touch.

#Privacy and #RightToExit

e-mail is a nearby-technology with planetary-scale connectivity, in a *socially* decentered way. Hold together by bubblegum and sticks. There is no project in sight that could "replace e-mail" (tm). We suggest to embrace and amend. Yes, it's a mess but it's also fun :)

#DeltaChat evolved according to needs of people under repression and continues to do so. The more ignorant and exchangeable we make #chatmail relays, the less their operators have to worry. Having metadata-less, fast and cheap instant messaging relays, that can also operate when 99% of the Internet vanishes in a region, is a key goal. Some way to go still but, already now, is there any other real-world solution that provides better service in internet-repressed regions in 2025?

@BellwetherFarm @syntaxseed @Jami
We don't have direct calls yet, but there are voice messages and "video chat invites". We have several times received feedback from users setting up Delta Chat in similar situation, so it might fit.

@risottobias
E-mail address is not a problem because you can always create a new address on any chatmail server. You don't need to use the address that you consider your "identity". In fact, we recommend using a dedicated mailbox for chatting.
@zeab @cassidy

@mro should be fine if it can run debian 12

@feld @fox84 "same team" is not quite true. Many delta chat teams have no hand in relay development. And vice versa.

We'd like to remind everyone that a self-hosted #chatmail relay is best shared in some wider than family circles. In crisis situations everbody does better when helping others.

A typical 1gb RAM chatmail relay VPS for 5-10 eur per month supports 50k+ daily users.

chatmail VPSes are stateless. You can wipe all disk state, reinstall and chatting will resume. Conversely, #deltachat does not keep or depend on any server state .Operators under pressure do not need to feel bad to hand over data.

Overheard last night from two users in #Cuba

user1: "the people are currently in need not only to save data plan but also to have more security in their conversations"

user2: "also stability. Right now the whole of Guantanamo is in blackout with problems in several radio-bases/cell-towers due to the lack of power/electricity and here I am talking like nothing / without breaking a sweat"

user2: "while WhatsApp doesn't even manage to connect"

#DeltaChat is for when centralization hits the fan

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

#deltachat designs are #OfflineFirst 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.

We don't see, or plan, a place for AI in our software stacks. A few notes.

Some attempts to use AI tooling provided nothing of value in the chatmail-core-UI stacks that produce the #deltachat store releases on all platforms.

Some in the community AI-generated a base #webxdc app and fixed bugs afterwards.That kind of worked and was borderline useful.

AI is pretty boring. We have more interesting work to do: evolve private resilient messaging by improving UX, networking, encryption, etc

@lutindiscret @fabrice we quite agree :) Single rust core is what allows to develop at a tiny fraction of the ~20 million USD yearly personal costs that signal foundation spends. We also don't spend 25 million yearly on Amazon, Google and cloudflare infrastructure which is bound to increase with more users. Everything is roughly a 100 times cheaper with delta dev and ops.

@fabrice having a rust core we consider a big advantage.

Most everybody else is trying to move their stacks implemented in java, swift, JavaScript at least partially to a shared rust basis. Signal has the cryptographic handling in rust now but otherwise three database-incompatible android/iOS/desktop impls of networking, parsing, chat/group/message logic.

One platform having flaws affects security of all chat groups so it's hardly a strength to have to care for three impls in three languages

@kill_9 fyi we have a plan for introducing forward secrecy that works reliably in decentralized, offline-first and multi-device settings. Nothing published about it but it's been conceptually checked from multiple cryptographic experts. We require some funding to do it. We are very aware of vast numbers of people insisting on forward security. But plain device seizure, compromised servers/clients and regional internet blockades and slowdowns are the actual everyday threats for many millions.

We are basically doing what #signal and in particular moxie refused to do or declares impossible: federation.

Both #email and #activitypub ecosystems are all about federation.

However, #deltachat is vertically centralized in that all UIs use the same #rust core which implements all networking, encryption, chat/group/message logic in a single centralized place. The now 40+ #chatmail mail relay network is driven from centralized code.

At each level replication and federation is built in.

@ip6li @derekmorr @doboprobodyne @cryptgoat Delta is NOT using gpg but a Rust implementation of OpenPGP, https://github.com/rpgp/rpgp ... and has several security audits. https://delta.chat/en/help#security-audits .. Both #signal and #deltachat use the same ED25519 Rust crate for identity keys.

Everyone returns to email in the end. We are there already. #whatsapp wants you to add your email to secure your account ... despite all the nay sayers and numerous well funded attempts and claims to kill #email not even WA can do it. #deltachat and #chatmail are about deep collab between people, projects and operators to evolve email from within. Really, it is not just about SMTP and IMAP and MIME and OpenPGP which are all exchangeable and can be improved ... Which we set out to do. Cheers.

#deltachat is secure against server-side group membership changes but for a very different reason than #signal which keeps encrypted group membership data in a central store.

Delta Chat has _no_ central store but implements a rigidly tested #p2p group membership model where servers play no role https://github.com/chatmail/models/tree/main/group-membership

Both signal and delta chat are safe against recently published attacks against #whatsapp that can add members to chats, breaking end to end encryption. https://arstechnica.com/security/2025/05/whatsapp-provides-no-cryptographic-management-for-group-messages