Signal Protocol + Curve25519 + ChaCha20-Poly1305

Private messaging.
Zero compromises.

Rail Gun is an end-to-end encrypted messaging app that keeps your conversations private. Your keys never leave your device.

Download NowOpen Web App
X3DH + Double RatchetSignal Protocol key exchange
Curve25519Modern elliptic curve cryptography
ChaCha20-Poly1305AEAD authenticated encryption

Why Rail Gun?

Built from the ground up with privacy and security as the foundation, not an afterthought.

Signal Protocol

Double Ratchet (KDF chains) + X3DH key exchange. Industry-standard end-to-end encryption with libsignal

Curve25519 Encryption

Modern elliptic curve cryptography (Curve25519) for key exchange and signatures via NaCl

ChaCha20-Poly1305

AEAD cipher providing authenticated encryption with associated data (AEAD) for message confidentiality

Group Encryption

Communities with encrypted channels using Signal Protocol group sessions and per-recipient keys

Perfect Forward Secrecy

Each message uses ephemeral keys. Compromised long-term keys cannot decrypt past messages

Open Source & Auditable

Full transparency on GitHub. Cryptographic implementations reviewed and auditable by security experts

Server Blindness

Backend sees only encrypted blobs (ChaCha20-Poly1305) and routing metadata. Content never exposed

Desktop-First Client

Native Electron app for macOS, Windows, Linux with local key storage and OS-level encryption

Download Rail Gun

Get Rail Gun for your platform and start messaging securely.

macOS

macOS 11+ (Intel & Apple Silicon)

Download

Windows

Windows 10+ (64-bit)

Download

Linux

Debian, Ubuntu, Fedora, AppImage

Download

Current version: 0.1.0 • Release notes

Try Rail Gun Web

Access Rail Gun from your browser—scan QR with your phone to sign in securely.

Open Web App
Security Built-In

Your messages are truly private

Rail Gun uses the same encryption protocol trusted by billions of users worldwide. Your private keys are generated locally and never touch our servers.

  • Signal Protocol (X3DH + Double Ratchet)
  • Perfect Forward Secrecy (PFS)
  • Extended Triple Diffie-Hellman (X3DH)
  • Double Ratchet Algorithm (KDF Chain)
  • libsodium / NaCl (Curve25519, ChaCha20-Poly1305)
  • HMAC-based Key Derivation Function (HKDF)
  • Local key generation and storage (never transmitted)
  • Open source and auditable (GitHub)
  • No phone number required
  • Metadata minimization (routing only)
  • Forward Secrecy & Backward Secrecy
  • Deniable Authentication

Verify Your Download

Always verify downloads to ensure they haven't been tampered with.

1. Import our GPG key:

gpg --keyserver keys.openpgp.org --recv-keys [KEY_ID]

2. Verify the signature:

gpg --verify SHA256SUMS.txt.asc SHA256SUMS.txt

3. Check the checksum:

# macOS/Linux sha256sum -c SHA256SUMS.txt --ignore-missing # Windows PowerShell Get-FileHash Rail-Gun-*.exe | Format-List
Full checksums available in SHA256SUMS.txt

Available Everywhere

Use Rail Gun on your favorite platform. Your encrypted messages sync securely across all your devices.

Desktop

Native apps for macOS, Windows, and Linux

Available Now

Web

Access from any browser with QR code sign-in

Coming Soon

Mobile

iOS and Android apps with seamless sync

In Development

Ready for private messaging?

Join thousands of users who trust Rail Gun for their secure communications. Download now and take back your privacy.

Download Rail GunTry Web Version