Quick start

Spin up a Velocity development environment, build the transport core, and understand the moving pieces without wading through the entire repository.

1. Prepare your environment

• Install the Rust toolchain via https://rustup.rs/ (the workspace pins versions in rust-toolchain.toml).
• Ensure Git and a modern PowerShell environment are present.
• Optional: keep CMake handy for future PQ crypto backends.

Verify the toolchain:

rustup show
cargo --version

2. Clone the workspace

# Replace the URL with your fork if needed
git clone https://github.com/AndrewCTF/ProjectVelocity.git
cd ProjectVelocity

git status

3. Build and test the transport core

cargo fmt
cargo clippy -p velocity-core --all-targets -- -D warnings
cargo test -p velocity-core

These commands keep formatting consistent, enforce warnings-as-errors, and run unit tests covering packet parsing, ALPN negotiation, and connection ID bounds.

4. Watch the UDP handshake loop

velocity_core::run_udp_handshake_loop shows how Initial packets can be parsed live from a UDP socket using Tokio:

use std::net::SocketAddr;
use velocity_core::{parse_packet, run_udp_handshake_loop, ParsedPacket};

#[tokio::main]
async fn main() -> std::io::Result<()> {
    run_udp_handshake_loop("127.0.0.1:44330", |peer: SocketAddr, packet: ParsedPacket<'_>| {
        println!("received {:?} from {}", packet.header.packet_type, peer);
    }).await
}

The handler executes synchronously today so higher-level crates can dictate scheduling strategies later.

5. Read the living spec

Refer to spec/protocol-draft.md for:

• Packet framing and message vocabulary.
• Hybrid cryptography profiles (light, balanced, fortress).
• ALPN negotiation and fallback semantics.
• Resumption, anti-downgrade strategies, and SSH transport mapping.

6. Next experiments