Open Source, Self-Hosted, Privacy Oriented
Receive gentle email check-ins. If you stop replying, your messages are delivered by email to the people you choose. Your words stay private with end-to-end encryption. A self-hosted dead man’s switch for delivering encrypted messages to your loved ones — when you’re gone or unresponsive.
True end-to-end encryption
The server can’t read your messages. By design.
Your messages are encrypted in your browser using each recipient’s public key before they ever leave your device. The server only stores encrypted blobs it cannot decrypt.
Recipients decrypt messages in their browser using their private key, protected by a passphrase only they know. No backdoors, no master keys, no exceptions.
🔐
Client-side encryption
Encrypted bef…
Open Source, Self-Hosted, Privacy Oriented
Receive gentle email check-ins. If you stop replying, your messages are delivered by email to the people you choose. Your words stay private with end-to-end encryption. A self-hosted dead man’s switch for delivering encrypted messages to your loved ones — when you’re gone or unresponsive.
True end-to-end encryption
The server can’t read your messages. By design.
Your messages are encrypted in your browser using each recipient’s public key before they ever leave your device. The server only stores encrypted blobs it cannot decrypt.
Recipients decrypt messages in their browser using their private key, protected by a passphrase only they know. No backdoors, no master keys, no exceptions.
🔐
Client-side encryption
Encrypted before upload
🖥️
Zero-knowledge server
Stores only ciphertext
🔑
Public-key cryptography
Only recipients can read
Open Source
BSL 1.1 licensed, fully auditable
Self-Hosted
Your server, your data
Zero-Knowledge
The server can’t read your messages
End-to-End Encrypted
XChaCha20-Poly1305 + Argon2id
How It Works
Three simple steps to protect what matters most. No complicated setup, no technical knowledge required.
💡
What if you miss a check-in?
No need to panic. You’ll receive multiple email reminders. After missing check-ins, there’s a grace period, then a cooldown window where you can cancel delivery with one click. You can also add a Trusted Contact who can confirm you’re alive but unreachable, delaying delivery by your chosen amount.
Built for Privacy, Designed for Humans
Every feature is designed with security and simplicity in mind. No compromises, no complexity.
Frequently Asked Questions
Got questions? Here are answers.
Use Cases
Real-world ways people can use LastSignal to protect sensitive information and share it at the right moment.