Testing and development

Regtest Network

For most testing and development, we recommend using the Regtest Network - a deployed test network maintained by Lightspark that is free to use and carries no real-world value.

What you can test on Regtest

• Spark Payments: Bitcoin and token payments using the Spark protocol
• Deposits: Receiving test Bitcoin from the Lightspark Regtest Faucet
• Withdrawals: Sending funds back to on-chain addresses
• Token Issuance: Creating and testing tokens using the SDK's issuing functionality

Getting started

1. Initialize the SDK using the default regtest config (no API key required)
2. Generate a Bitcoin receiving address
3. Request funds from the faucet to your generated address
4. Test all Spark-related functionality in a controlled development environment

Mainnet testing

Some features rely on live networks that Regtest doesn't reproduce. Test these on Mainnet with small amounts: use real satoshis, but keep transaction values very low while verifying the flows work correctly.

Lightning payments

The Regtest Network doesn't have a developed Lightning Network, so test Lightning send and receive flows on Mainnet.

Stable balance and USDC/USDT

The stablecoin assets are only available on Mainnet:

• USDB is the Spark-native stablecoin behind Stable Balance.
• USDC and USDT are cross-chain assets. Use Send USDC/USDT to pay recipients on their native chains. The cross-chain providers operate against live external networks and have no testnet equivalent.

Test these integrations on Mainnet with small amounts.

Development best practices

• Start with Regtest for most development and testing
• Use Mainnet for Lightning, stable balance, and USDC/USDT testing
• Test all payment types you plan to support in your application