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Launch your own branded stablecoin, backed 1:1 by USDC reserves on Coinbase, with instant onchain liquidity. This documentation is for technical partners integrating with the Custom Stablecoins swap program. You’ll find everything you need to construct and submit swap transactions from your application or smart contract.

Use cases

Branded payment tokens

Launch your own stablecoin for in-app payments and rewards while maintaining USDC liquidity

Loyalty and rewards

Issue branded tokens as rewards that users can seamlessly convert to USDC

Gaming economies

Create in-game currencies backed by USDC with instant redemption

DeFi protocols

Integrate custom stablecoins into DeFi applications with guaranteed USDC liquidity

Key features

  • 1:1 USDC backing: Fully backed by USDC reserves on Coinbase
  • Instant swaps: Single-transaction settlement
  • Predictable pricing: Fixed 1:1 ratio with no slippage surprises
  • Multi-chain support: Available on Solana and Base (EVM)
  • Flexible integration: Use via Cross-Program Invocation (Solana) or direct smart contract calls (EVM)
  • Multi-decimal support: Automatic normalization between tokens with different decimal precision

Supported networks

NetworkUse caseContract type
Solana DevnetTesting and developmentAnchor program
Solana MainnetProduction useAnchor program
Base SepoliaTesting and developmentEVM smart contract
Base MainnetProduction useEVM smart contract

Onchain liquidity

Stableswapper is the onchain liquidity program that powers instant swaps between USDC and any Custom Stablecoin issued through the program. It is deployed on both Solana and Base, providing the settlement layer partners need to let their users move freely between custom tokens and USDC. Learn how to integrate swaps into your application.

How it works

The Stableswapper program maintains a liquidity pool with reserves for each supported token.
1

User initiates swap

The input token is transferred to the contract
2

Validation

The program checks the allowlist (if enabled), validates slippage protection, and applies any configured fee
3

Settlement

The equivalent amount of the output token is sent to the destination address
Swaps settle atomically in a single transaction at a 1:1 ratio before fees, with automatic decimal normalization between tokens with different precision.

Concepts

ConceptDescription
PDA (Program Derived Address)Deterministic on-chain account owned by the program — used for the pool, vaults, and whitelist
VaultA PDA that acts as the logical owner for a token’s reserves within the pool
Vault Token AccountThe SPL token account that actually holds the token reserves for a given vault
ATA (Associated Token Account)A user’s standard token account for a given mint, derived deterministically from their wallet
WhitelistAn optional on-chain list of authorized wallet addresses. When enabled, only listed addresses can execute swaps
SlippageThe minimum acceptable output amount (min_amount_out). Protects against fee changes between transaction construction and execution