Preparing Your Environment

Prerequisites

• Rust & cargo

Creating your Project Structure

• Make a new cargo project:

cargo new nym-cosmos-service

• Create the following directory structure and files:

.
├── Cargo.toml
├── bin
│   ├── client.rs
│   └── service.rs
└── src
    ├── client.rs
    ├── lib.rs
    └── service.rs

3 directories, 6 files

• Add the following dependencies to your Cargo.toml file:

[dependencies]
clap = { version = "4.0", features = ["derive"] }
cosmrs = "=0.15.0"
tokio = { version = "1.24.1", features = ["rt-multi-thread", "macros"] }
serde = "1.0.152"
serde_json = "1.0.91"
anyhow = "1.0.72"

These are non Nym-specific dependencies for the project. clap is for setting up the CLI commands, cosmrs for cosmos-specific types and functionality, tokio for the async/await environment, and serde for (de)serialisation. anyhow is for catch-all error handling.

• Next add Nym-specific dependencies. Since these libraries are not yet on crates io then you need to import them from the Nym monorepo:

nym-sdk = { git = "https://github.com/nymtech/nym", rev = "85a7ec9f02ca8262d47eebb6c3b19d832341b55d" }
nym-sphinx-addressing = { git = "https://github.com/nymtech/nym", rev = "85a7ec9f02ca8262d47eebb6c3b19d832341b55d" }
nym-validator-client = { git = "https://github.com/nymtech/nym", rev = "85a7ec9f02ca8262d47eebb6c3b19d832341b55d" }
nym-bin-common = { git = "https://github.com/nymtech/nym", rev = "85a7ec9f02ca8262d47eebb6c3b19d832341b55d" }
nym-sphinx-anonymous-replies = { git = "https://github.com/nymtech/nym", rev = "85a7ec9f02ca8262d47eebb6c3b19d832341b55d" }

The sphinx dependencies are for packet- and address-related functionality, the validator-client for Nyx blockchain specific configs, common for client logging, and the sdk for SDK functionality: creating and managing client storage and connections, and sending and receiving messages to and from the mixnet.

• Finally add the following underneath your [dependencies]:

[[bin]]
name = "client"
path = "bin/client.rs"

[[bin]]
name = "service"
path = "bin/service.rs"

This defines multiple binaries to run in a single cargo project, as outlined here.