Write it down.
Then let it burn.

Encrypted in your browser before it leaves. The server keeps only ciphertext, and destroys it the moment it's read.

Signed, sealed,
self-destructing.

Passphrase set. Send it separately — another app, a call, or in person.

Everything after # is the decryption key. It never reaches the server, so a lost link can't be recovered by anyone.

Nothing left
but ash.

This secret has already been read, has expired, or never existed. Each link opens only as many times as its sender allowed.

Something's off.