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# Postcard From 2035: Your Chats Got Opened. Ours Are OK.
- URL: https://z-text.org/postcard-from-2035-harvest-now-decrypt-later/
- Published: 2026-10-12T10:05:04.000Z
- Updated: 2026-10-13T08:47:09.000Z
- Description: A postcard from 2035: someone copied your encrypted chats in 2026, waited, and opened them with a quantum computer. Here is what "harvest now, decrypt later" means, and how Z-TEXT protects a chat today.
- Author: Eric Pierrot - Founder, Z-TEXT LLC — building privacy tools without phone numbers, email, or metadata.
- Tags: Message from 2035, Quantum, Privacy, zk-SNARKs, Z-TEXT

A postcard just arrived from 2035\. It's a joke. The warning inside is not.

Z-TEXT is a privacy messenger built on the BitcoinZ blockchain. It needs no phone number, no email and no SIM. Your identity is 24 words.

This is the first card of a new series: **Message from 2035**. A time traveler looks back at 2026, and laughs. Every card hides one true fact.

Card #1 is about quantum computers.

![Vintage postcard from 2035 to 2026 with a Z-TEXT bird stamp and a "Quantum-resistant" postmark. Message: your encrypted chats were copied, waited, and opened by a quantum attack in 2035; Z-TEXT chats are OK.](https://storage.ghost.io/c/fd/15/fd15bb3d-d8d8-469e-8b80-b94dae7aa4cd/content/images/2026/10/ZText2035Postcard01.png)

Message from 2035 · #1\. A joke on the front, a real fact on the back.

## ❓ What does the postcard say?

"Dear 2026, your encrypted chats? Someone copied them. Waited. In 2035, a quantum attack opened them. Ours are OK."

The year 2035 is invented. The method is real.

## ❓ What is "harvest now, decrypt later"?

**"Harvest now, decrypt later"** means collecting encrypted data today and storing it until a future technology can break it. (Source: [Wikipedia](https://en.wikipedia.org/wiki/Harvest%5Fnow,%5Fdecrypt%5Flater?ref=z-text.org))

A **quantum computer** is a new kind of computer. A large one could break the public-key math that protects most encrypted chats today.

The attacker doesn't need that computer now. The attacker only needs to keep a copy and wait.

Europol warned about this on 7 October 2026\. We explained it here: [Europol's Quantum Warning: What It Means for Messaging](https://z-text.org/europol-quantum-warning-harvest-now-decrypt-later/).

## ❓ Why does it matter more on a blockchain?

Z-TEXT stores messages on the BitcoinZ blockchain. A blockchain is permanent: anyone can keep a copy, forever.

So a blockchain messenger must plan for the future attacker from day one. Permanence and quantum resistance go together.

## ❓ How does Z-TEXT protect a chat today?

Every Z-TEXT one-to-one chat starts with a **hybrid key exchange**: ML-KEM-768 together with classical X25519\. Live since version 3.7.0.

**ML-KEM-768** is a quantum-resistant key exchange standardized by NIST in August 2024 as FIPS 203\. (Source: [NIST FIPS 203](https://csrc.nist.gov/pubs/fips/203/final?ref=z-text.org))

The message itself is encrypted with AES-256-GCM. On the blockchain, zk-SNARKs hide the sender, the receiver and the amount.

A copy taken today stays locked, even for an attacker who waits.

## ❓ What is not quantum-resistant yet?

Honest answer, so the postcard stays fair:

| Z-TEXT part                       | Quantum-resistant today?                 |
| --------------------------------- | ---------------------------------------- |
| One-to-one chat key exchange      | Yes: ML-KEM-768 + X25519                 |
| Message signatures                | Not yet: classical Ed25519               |
| BitcoinZ shielded layer (Sapling) | Not yet: depends on the BitcoinZ network |
| Wallet, Channels, Communities     | Not yet                                  |

The Z-TEXT app has not been independently audited yet. A public bug bounty is open.

## ❓ What is "Message from 2035"?

A series of 10 postcards. One per day. A time traveler laughs at 2026: phone numbers, deleted accounts, open servers.

Each card is a joke on the front and a fact on the back. Next card: why nobody asks for your phone number in 2035.

Z-TEXT runs on Android, macOS, Windows and Linux: [z-text.com/downloads](https://z-text.com/downloads?ref=z-text.org). BitcoinZ lives at [getbtcz.com](https://getbtcz.com/?ref=z-text.org).

### Sources

1. [Wikipedia, Harvest now, decrypt later](https://en.wikipedia.org/wiki/Harvest%5Fnow,%5Fdecrypt%5Flater?ref=z-text.org)
2. [NIST, FIPS 203 (ML-KEM), August 2024](https://csrc.nist.gov/pubs/fips/203/final?ref=z-text.org)
3. [Z-TEXT, Europol's Quantum Warning: What It Means for Messaging](https://z-text.org/europol-quantum-warning-harvest-now-decrypt-later/)
4. [Z-TEXT](https://z-text.com/?ref=z-text.org) · [BitcoinZ](https://getbtcz.com/?ref=z-text.org)

Keywords: quantum-resistant messaging app · private messaging app · blockchain messenger · zero-knowledge proof messenger · no phone number messaging app · harvest now decrypt later · ML-KEM-768 · Signal alternative

[👉 No Phone. No Email. No SIM. Zero Metadata. Just Z-TEXT. ](https://z-text.com/packages?ref=z-text.org)