High-performance peer-to-peer & edge networking module for Vix.cpp.
Designed for offline-first systems, unstable networks, and secure distributed runtimes.

This module powers Vix’s sync engine (WAL / outbox) and forms the transport backbone of the ecosystem.

✅ TCP peer connections
✅ Secure handshake lifecycle
✅ Per-peer session state
✅ Peer discovery (UDP broadcast / multicast)
✅ HTTP bootstrap (registry pull / announce)
✅ Runtime peer & handshake statistics
✅ Clean shutdown & signal handling
✅ Modular, production-shaped architecture

This is not a toy P2P example.

modules/p2p/
├── include/            # Public P2P API (Node, Peer, Protocol, Crypto, …)
├── src/                # Implementation
├── tests/
│   ├── manual/         # Manual integration tests
│   │   ├── main.cpp    # p2p_demo (real runtime demo)
│   │   └── registry.py # HTTP bootstrap registry (test server)
│   └── CMakeLists.txt
├── build/              # Build output
│   └── tests/
│       └── p2p_demo    # Compiled demo binary
├── CMakeLists.txt
├── README.md
├── CHANGELOG.md
└── LICENSE

The real executable demo lives here after build:

cmake -S . -B build -DVIX_P2P_BUILD_TESTS=ON
cmake --build build -j
build/tests/p2p_demo

It spins up a full P2P node with:

• listening socket
• optional outbound connections
• discovery
• bootstrap
• live stats

./build/tests/p2p_demo --id A --listen 9001

./build/tests/p2p_demo --id B --listen 9002 --connect 127.0.0.1:9001

./build/tests/p2p_demo \
  --id B \
  --listen 9002 \
  --connect 127.0.0.1:9001 \
  --connect-delay 8000

./build/tests/p2p_demo --id A --listen 9001 --run 20

Printed periodically while running:

peers_total=2
peers_connected=1
handshakes_started=1
handshakes_completed=1

Final stats are always printed on exit.

--discovery on
--disc-mode broadcast | multicast
--disc-port 37020

--bootstrap on
--registry http://127.0.0.1:8080/p2p/v1
--announce on

A minimal test registry is provided in:

tests/manual/registry.py

• Explicit handshake state machine
• Per-peer session lifecycle
• Control messages remain plaintext (safe bootstrapping)
• Designed for AEAD encrypted payloads
• Ready for secure WAL / sync traffic

• C++ backend engineers
• Distributed systems developers
• Offline-first / local-first builders
• Edge & P2P networking enthusiasts
• Anyone who wants real P2P, not fake examples

• Clean production-oriented P2P design
• Minimal but realistic
• Built for unstable networks
• Reusable as a base for:
  • sync engines
  • mesh networks
  • decentralized runtimes
• Actively used inside Vix.cpp

✔️ Actively developed
✔️ Manually tested
✔️ Used internally
🚧 Continuously evolving

If this module helped you understand how real P2P in C++ should look,
leave a ⭐ it genuinely helps the project grow.