End-to-end encrypted
Messages are encrypted on your device before they leave. The server routes ciphertext it cannot read, built on Signal's own cryptography.
End-to-end encrypted
Private messaging that answers to no one.
Built on the Signal Protocol. No phone number, no email, no account - your private identity key stays on your device.
No phone number
No tracking
Open source
AR
Ana Ruiz
Verified · end-to-end encrypted
Messages to Ana are secured with end-to-end encryption.
Can you send the address here? I do not want it sitting in email.
9:18
Sure. 14 Wren Lane, side gate. I will meet you there at 7.
9:20
Got it. Thanks.
9:22
Message Ana...
The basics
What Seald gives you
No phone number
Your private identity key is generated on-device. No phone, email, or profile to hand over.
No tracking, ever
No telemetry, no analytics, no cookies - not even on this website. The server stores only the routing and abuse-prevention metadata described in the threat model.
Why Seald
Most messengers start by registering you. Seald starts by creating keys.
End-to-end encryption protects message contents, but the account layer still matters. Phone numbers, profiles, contact discovery, usernames, recovery flows, and device records can become durable identity metadata even when nobody can read your messages.
The tradeoff is deliberate.
Seald is less convenient than apps with phone-number discovery. There is no central account to search, reset, or recover through email. That is the point: less account infrastructure means less identity data for the server to hold.
Account model
Requires a mobile number and account profile. Message contents are end-to-end encrypted, but the service still maintains account, device, usage, and interaction metadata.
Account model
Signal
Excellent cryptography and much stronger privacy protections, but it still begins with phone-number registration. Usernames help you connect without sharing the number; they do not remove registration.
Seald model
Device key
Your identity is generated on your device. You connect by sharing an invite link or scanning a contact code, not by registering a phone number, email address, or public profile.
How do people find me?
You share an invite link or scan a contact code. That exchanges the public material needed to start an encrypted conversation without creating a searchable account directory.
What does the server know?
The server sees routing and connection metadata such as recipient fingerprints, timing, and volume. It does not get your message contents, private keys, contact list, phone number, email address, or profile name.
What if I lose my device?
There is no email reset for a cryptographic identity. Safer migration and recovery can be added, but not through a server-side account takeover path.
Is sealed sender live?
The server and crypto core can handle sealed-sender envelopes that store no sender identity. Full client activation is still staged, so Seald does not claim every message uses that path yet.
How it works
Your messages, your keys
Every message is encrypted on your device before it is sent. The server never sees the contents - it just delivers an opaque blob only the recipient can open.
1
Encrypted on your device
Your message is encrypted with the Signal Protocol before it leaves. Your private keys are generated on-device and never leave it.
2
Server routes ciphertext
The server receives an opaque blob. It knows where to deliver it, but cannot read, modify, or analyse what is inside.
3
Decrypted by the recipient
Only their device holds the private keys. The Triple Ratchet derives fresh keys for every message, with post-quantum protection.
Transparency
What we do not know about you
Messaging apps can claim anything. Here is what our server actually sees versus what it cannot - trust the architecture, not us.
What the server sees
- That an IP address connected
- Connection timing and duration
- Traffic volume between endpoints
- Recipient fingerprints
What the server cannot see
- What you said or sent
- Your private keys
- Your contact list
- Your name or profile
- When you read messages
Sealed sender is staged, not default yet. The server and crypto core can handle sealed-sender envelopes that store no sender identity; full client send and receive activation is still in progress.
Under the hood
Audited libraries, not marketing claims
Protocol
Signal · PQXDH
Triple Ratchet with post-quantum key exchange, using libsignal directly.
Identity
Curve25519 · XEdDSA
Private key stays local. Public identity and prekeys let contacts start sessions without a registrar.
Server
Bun + Rust
Network I/O and storage verification split across a Unix domain socket.
Storage
SQLite · WAL
The simplest tool for the job - a small, auditable surface.
Trust & verification
Open source and security
Seald is built for the people who will read the code, threat model, and audit scope before they trust it.
Source
Open source from day one
The server, clients, protocol docs, and threat model are intended to be public before launch.
Audit
Audit planned
The priority scope is the Rust crypto core and storage service: the small surface where correctness matters most.
Builds
Reproducible builds planned
Release artifacts should be independently verifiable, not just downloaded on faith.
Get started
Download Seald
No account to create. Download, open, and you exist - your identity is generated on your device in seconds.
macOS
Coming soon
In developmentmacOS 12 or later
iOS
Coming soon
In developmentNative Swift · iOS 15+
Android
Coming soon
In developmentNative Kotlin · Android 8+
Honest caveat: Seald has not yet undergone an independent security audit. Do not rely on it for high-threat communications until an audit report is published - we would rather earn trust through transparency than claim it prematurely.