Spark Stables Bridge

Spark Stables is a quote-based bridge that supports inbound USDC -> USDB on Spark and outbound USDB -> USDC to supported chains.

Components

User wallet (Solana/EVM or Spark): Sends USDC on the source chain or USDB on Spark.
Bridge SDK (spark.stables): Quote, submit, and status helpers.
Bridge API: Issues quotes, verifies deposits, and orchestrates minting/transfers.
Source chain (USDC): Receives inbound deposits.
Spark: Receives inbound USDB and is the source for outbound USDB.
Brale: Converts USDC to/from USDB and transfers to the correct network.
Destination chain (USDC): Receives outbound transfers.

Inbound (USDC -> USDB): Outbound (USDB -> USDC):

processing: deposit submitted, waiting for verification.
confirming: tx found, waiting for chain confirmations.
minting: Brale transfer in progress.
completed: USDB sent to Spark (inbound) or USDC sent to destination chain (outbound).
failed: terminal failure.

Quote status (when polling by quoteId):

Amounts are strings in smallest units (6 decimals).
Only quote needs direction; other endpoints infer it from ids or tx hashes.
Inbound uses sourceChain; outbound uses destinationChain + destinationAddress.
Quotes expire; the deposit address is bound to the quote.
Processing is idempotent; it is safe to retry process.
Supported chains: solana, base, polygon, arbitrum, optimism, ethereum.