SYSTEM ARCHITECTURE • EPHEMERAL ZERO-KNOWLEDGE SPECIFICATION

Engineered for Absolute Anonymity

PrivyChat is an ultra-secure, memory-volatile spy messenger designed from the ground up for environments where digital surveillance, metadata harvesting, and physical snooping compromise human liberty.

Six Layers of Uncompromising Defense

Every packet, byte, and user interaction is wrapped in mathematical guarantees.

100% RAM-Only Engine

Zero hard drives. Zero databases. Zero server write operations. Every room and user state lives solely in volatile heap memory. If power is interrupted, 100% of room history disappears instantly and irreversibly.

No persistent disk logs

AES-256-GCM + PBKDF2

Messages are encrypted in your browser using the native Web Crypto API with 256-bit AES-GCM and unique 96-bit initialization vectors (IV) per payload. Keys are derived through 100,000 iterations of PBKDF2 SHA-256.

End-to-End browser encryption

WiFi & Bluetooth Mesh

Communicate without global internet access. Connect via local WiFi/Hotspot subnet discovery, Web Bluetooth (BLE) proximity detection, or 100% air-gapped QR Code camera handshakes over direct WebRTC DataChannels.

Zero internet offline mode

Physical OPSEC Suite

Defend against physical observers with Ghost Mode (heavy hover-to-reveal blur), functional scientific Calculator disguise (PIN unlocked with 1337=), and Decoy Vault redirection.

Anti-snoop screen shielding

Invisible Ink Steganography

Embed encrypted messages inside innocent PNG/JPEG image carrier pixels using Least Significant Bit (LSB) encoding. To inspectors, it's a regular photo; to PrivyChat agents with the passphrase, it's an encrypted briefing.

In-browser pixel manipulation

Self-Destruct & Panic Purge

Set ephemeral burn timers (5s to 60s, Burn-on-Read). When triggered or when the Panic Button is pressed, encryption keys are wiped from memory, session DOM is scrubbed, and the browser is instantly redirected.

One-click nuclear erase
CRYPTOGRAPHIC LIFECYCLE

How Zero-Trace Messaging Operates

01

Ephemeral Key Generation

Upon entering a room, your browser generates or derives a 256-bit symmetric AES key in memory. The key is never transmitted over the network.

02

Client-Side Cipher

Text, voice notes, and files are encrypted locally with a fresh random 12-byte IV. Only unreadable ciphertext leaves your device.

03

Blind RAM Transit

The server acts as a blind relay. It holds ciphertext in temporary RAM for sub-50ms transmission to recipients, without storage or inspection.

04

Local Burn & Memory Zero

Recipient decrypts locally. Once read or after the expiration timer fires, decrypted buffers are zeroed out and garbage-collected.

CREATOR & LEAD ARCHITECT

Behind PrivyChat

Pratham Kumar

ADMIN & FOUNDER

Lead Cryptography Engineer • Full-Stack Systems Architect

Node.js / Express Web Crypto API (AES-GCM / PBKDF2) WebRTC DataChannels Socket.IO Clustering Web Bluetooth (BLE) API Canvas Steganography
"Privacy isn't about having something to hide; it's about having the fundamental right to communicate without corporate surveillance or state interception. PrivyChat proves that real-time communication can exist with zero digital footprint."
Zero-Knowledge Proof

Designed the memory-only message lifecycle preventing any forensic residue on storage mediums.

Air-Gapped Mesh Engine

Created WiFi hotspot subnet discovery, Web Bluetooth pairing, and QR SDP exchange for offline survival.

CROSS-PLATFORM • ANDROID NATIVE

📱 PrivyChat Android App

The full PrivyChat experience — now offline-first on Android. Communicate without any internet via local WiFi, Bluetooth mesh, or air-gapped QR handshakes.

Mobile Architecture

  • Flutter + Dart — native Android app compiled to ARM binary for maximum performance.
  • Dual-layer P2P Mesh — WebRTC DataChannels + Socket.io relay for seamless local-first communication.
  • ECDH P-256 + HKDF SHA-256 — Ephemeral key exchange with RFC 5869 key derivation, pure Dart implementation.
  • AES-256-GCM with AAD — Every message encrypted with authenticated additional data for tamper detection.
  • Zero Persistent Storage — Messages never written to device storage. Volatile in-memory only.

Offline Connectivity Modes

Local WiFi / Hotspot Mesh

Auto-discovers peers on the same router or mobile hotspot. No internet required. Range: 50–100m.

Bluetooth Low Energy (BLE)

Proximity pairing with RSSI signal tracking. Works without WiFi. Range: 10–30m.

Air-Gapped QR Optical Beam

Camera-to-screen SDP exchange. 100% zero network. Works in Faraday cages and RF-denied zones.

📲 Download PrivyChat for Android

Works on Android 8.0+. Built with Flutter. APK hosted on GitHub Actions.

Install APK (Android)

Open-Source & Cryptographically Verifiable

Never trust proprietary black-box messengers. PrivyChat's frontend and backend code is 100% open for independent audit on GitHub.

View Repository on GitHub