SnapSend - Zero-Knowledge Secret Sharing

SnapSend is a zero-knowledge secret-sharing app, share a password, API key, or note that destroys itself after it’s read.

🔗 Live app: https://www.twine.net/signin

How it works

The secret is encrypted in your browser with AES-256-GCM before anything ever touches the network. The decryption key lives only in the URL fragment (after the #), so it’s never transmitted to or stored by the server, the server only ever holds ciphertext it can’t read.

Key features

• Zero-knowledge encryption - AES-256-GCM performed client-side; the server never sees plaintext or the key
• Burn after reading - the secret is destroyed atomically after the last allowed view, with no race conditions or leftovers
• Auto-expiry - configurable TTL (5 minutes to 1 week) removes the secret even if the link is never opened
• View limits - set a max number of views before the link self-destructs

Tech stack

• Frontend: Next.js, TypeScript
• Backend: .NET 10
• Storage: Redis (TTL-native, ephemeral by design)

Why I built it

Most “secure” paste/share tools still trust the server with your plaintext at some point. SnapSend moves encryption entirely to the client, so even a compromised or subpoenaed server has nothing readable to hand over.