kaspa-rust-starter

🦀 Kaspa Rust Starter Kit

A small Rust starter kit for building on Kaspa testnet-10. Four binaries take you from generating a wallet all the way to spending a covenant. Nothing here needs a local node; it all goes through the public Resolver.

What's inside

Binary	What it does	Needs funds?
wallet	Generate a wallet (keypair + testnet address)	no
connect	Connect via Resolver, read your balance	no
send	Build, sign, and broadcast a transaction	yes
covenant_p2sh	Lock funds in a pay-to-script-hash covenant, then spend it	to spend

The shared bits (connect, keypair, address, .env) live in src/lib.rs.

Prerequisite: install Rust

This is a one-time setup of the language itself, separate from the kit. You only do it once per machine.

Install Rust via rustup. rust-toolchain.toml pins the toolchain to 1.91.0, and rustup fetches it automatically on the first cargo command. A Rust installed some other way (Homebrew, apt, the system package manager) won't honor the pin and may be too old. Check:

rustup --version
cargo --version

If you already have rustup but an older default, run rustup update.

Set up the kit

cd kaspa-rust-starter
cp .env.example .env
cargo build

Run it (in order)

# 1. Make a wallet. Copy the printed private key into .env (KASPA_PRIVATE_KEY=...).
cargo run --bin wallet

# 2. Fund the address from the faucet (see below), give it a few seconds, then check it landed.
cargo run --bin connect

# 3. Send 1 KAS back to yourself and watch it in the explorer.
cargo run --bin send

# 4. Print a P2SH covenant address; paste it into the faucet to fund it, then spend it.
cargo run --bin covenant_p2sh
cargo run --bin covenant_p2sh -- --spend

KASPA_PRIVATE_KEY is read from .env or the environment.

The send and covenant_p2sh binaries submit a transaction and print its id. Re-run connect to watch the balance change, or look the tx id up in the explorer.

Reference

• Network: testnet-10. Addresses start with kaspatest:.
• Faucet: https://faucet-tn10.kaspanet.io/. Paste your kaspatest: address to get test KAS.
• Explorer: https://tn10.kaspa.stream/ — search your address or a tx id.
• Units: amounts are in sompi, where 1 KAS = 100,000,000 sompi.
• No node required: Resolver::default() finds a public testnet-10 node for you.
• Docs: https://docs.kaspa.org

How it fits together

• Connect: KaspaRpcClient::new(WrpcEncoding::Borsh, None, Some(Resolver::default()), Some(network_id), None), then client.connect(...), with network_id = NetworkId::with_suffix(NetworkType::Testnet, 10).
• Wallet: a secp256k1::Keypair turns into Address::new(Prefix::Testnet, Version::PubKey, &xonly_pubkey).
• Send: get_utxos_by_addresses gives you UTXOs; build a Transaction with pay_to_address_script outputs, sign it via sign(MutableTransaction::with_entries(tx, entries), keypair), and call submit_transaction.
• Covenants: ScriptBuilder builds a redeem script, then pay_to_script_hash_script plus extract_script_pub_key_address turn it into a spendable P2SH address. Spending reveals the script and a signature in the input's unlock script.

Where to go next

• Send to a different address by editing to in src/bin/send.rs.
• Add covenant rules (for example, enforcing the recipient or amount) in build_redeem_script in src/bin/covenant_p2sh.rs.
• Reference code in rusty-kaspa (pinned to the v2.0.1 tag): rpc/wrpc/examples/simple_client, rothschild, and crypto/txscript/examples/covenants.rs.