Use the public Radiant testnet

The 5-minute quickstart runs on regtest — a private chain on your own machine. That is the recommended way to build and iterate: it’s deterministic, free, needs no peers, and you mine and fund blocks yourself with pyrxd regtest mine / pyrxd regtest fund. Reach for the public testnet only when you specifically need a shared network — testing against other people’s transactions, a wallet, or an indexer over real P2P/finality.

Reliability note (verified 2026-06-11). Radiant’s public testnet faucet is community-run and was returning a gateway error when this guide was written. Regtest has no external dependency and is the path that always works; treat testnet as best-effort. If the faucet below is down, ask in the official Radiant channels (linked from https://radiantblockchain.org) for the current testnet faucet — do not assume a specific URL is canonical.

1. Get a testnet-capable node binary

Testnet runs the same radiantd as mainnet, selected with -testnet. Download the latest official release binary from Radiant-Core releases (the radiant-<version>-linux-x64.tar.gz daemon bundle), or use the Radiant Core GUI. Run it on testnet:

$ radiantd -testnet -server -txindex=1 \
    -rpcuser=you -rpcpassword=change-me -rpcbind=127.0.0.1 -rpcallowip=127.0.0.1

The SCRIPT_SECURITY_UPGRADE consensus rules (the 64 MB per-script stack budget added in v3.1.x) are already active on testnet from block 1, so testnet is the closest public mirror of post-upgrade mainnet behaviour — a good reason to validate covenant-heavy work here before mainnet.

2. Point pyrxd at testnet

pyrxd’s CLI config takes a network of mainnet | testnet | regtest (~/.pyrxd/config.toml, see pyrxd.cli.config). Set network = "testnet" and put your testnet node’s RPC/ElectrumX endpoints under [networks.testnet]. Testnet addresses use the testnet version bytes, so a key reconstructed with PrivateKey(wif) from a testnet wallet derives a testnet address — the same flow as the quickstart, just on the shared chain.

3. Fund a testnet address

Testnet coins have no value and come from a faucet (you can’t mine them on demand the way pyrxd regtest fund does on your private chain). The community faucet has been hosted at faucet-testnet.radiant4people.com (the mainnet sibling, faucet.radiant4people.com, was live at the time of writing). Paste a testnet address; if the faucet is unavailable, the official Radiant Discord is the place to ask for testnet RXD or the current faucet endpoint.

Once funded, every other recipe — minting a Glyph, building a covenant, running a swap leg — works the same as on regtest; only the network and the source of coins change.

When to use which

	regtest (quickstart)	public testnet
Coins	pyrxd regtest fund (instant, unlimited)	community faucet (best-effort)
Blocks	you mine (pyrxd regtest mine)	shared, ~real timing
Peers / P2P	none (isolated)	real network
Determinism	total	none
Best for	building & iterating, CI, the quickstart	shared-network / wallet / indexer testing

For almost all development, stay on regtest. Graduate to testnet only for the shared-network behaviour regtest can’t give you.