---
title: "Nym Rust SDK: Mixnet Messaging Module"
description: "Use the Nym Rust SDK Mixnet module to send messages through the mixnet. Covers builder patterns, custom topologies, SOCKS proxy, and anonymous replies."
schemaType: "TechArticle"
section: "Developers"
lastUpdated: "2026-03-13"
---

# Mixnet Module

import { Callout } from 'nextra/components';

The `mixnet` module is the core of the Nym SDK. It provides [`MixnetClient`](https://docs.rs/nym-sdk/latest/nym_sdk/mixnet/struct.MixnetClient.html) for connecting to the Nym Mixnet, sending messages through Sphinx packet encryption and 5-hop routing, and receiving reconstructed messages on the other side.

<Callout type="warning">
Messages are individually routed through the Mixnet with no guaranteed ordering or persistent connections. If you want familiar socket-like I/O (`read`/`write`), use the [Stream module](./stream) instead. See the [Tour](./tour) for how the two approaches compare.
</Callout>

## Two operating modes

The client operates in one of two mutually exclusive modes:

**Message mode** (default): send and receive raw message payloads:
```rust
use nym_sdk::mixnet::{self, MixnetMessageSender};

let mut client = mixnet::MixnetClient::connect_new().await.unwrap();

// Send a message
client.send_plain_message(*client.nym_address(), "hello").await.unwrap();

// Receive messages
if let Some(msgs) = client.wait_for_messages().await {
    for msg in msgs {
        println!("Got: {}", String::from_utf8_lossy(&msg.message));
    }
}

client.disconnect().await;
```

**Stream mode:** persistent `AsyncRead + AsyncWrite` channels. See the [Stream module](./stream) for details.

<Callout type="info">
Stream mode is activated by calling `open_stream()` or `listener()`. Once active, message-mode methods return `Error::StreamModeActive`. This is a one-way transition.
</Callout>

## API reference

- [API reference on docs.rs](https://docs.rs/nym-sdk/latest/nym_sdk/mixnet/): full architecture documentation, all types, builder methods, traits, and configuration options
- [Examples on GitHub](https://github.com/nymtech/nym/tree/develop/sdk/rust/nym-sdk/examples): runnable examples covering simple send/receive, builder patterns, custom topologies, SOCKS proxy, anonymous replies, and more

Run any example with:
```sh
cargo run --example <example_name>
```

## Next steps

- [Tutorial: Send your first private message](./mixnet/tutorial): step-by-step guide covering sending, receiving, SURBs, and persistent identity
- [Troubleshooting](./mixnet/troubleshooting): common issues with logging, empty messages, and client lifecycle
- [Stream module](./stream): if you need persistent bidirectional byte channels
