Cross-chain smart contracts and backend framework powering Web3-to-card payments.
Rain bridges Web3 payments with traditional card-issuing rails, enabling users to spend stablecoins through conventional payment networks.
57Blocks built Rain’s blockchain foundation, delivering smart contracts for settlement and liquidity, cross-chain interoperability, and a resilient backend architecture to support high-volume transactions across Solana, Stellar, and EVM environments.
01Smart contract development
Led contract migration from EVM to Solana and Stellar, ensuring parity in logic and security across ecosystems.
02Signature authorization
Implemented on-chain signature verification systems — EIP-712-style authorization on Solana and multi-signature management on Stellar — validating privileged operations before execution.
03Multi-chain system abstraction
Refactored the backend to decouple EVM-specific components, enabling modular integration of Solana and Stellar.
04Asynchronous transaction throughput
Transitioned from sequential to concurrent task handling, supporting simultaneous multi-network transactions.
05Idempotency & concurrency control
Added safeguards against duplicate submissions and race conditions during concurrent operations.
06Resource & fault management
Introduced granular rate limiting, RPC fallback, automated recovery, and fault-tolerant event handling.
Unified multi-chain settlement layer supporting Solana, Stellar, and EVM networks.
High-throughput, fault-tolerant transaction processing under production-scale load.
Secure off-chain authorization and verified on-chain execution for card payment operations.
Strengthened backend resilience and resource efficiency for the stablecoin-to-card payment flow.
Rain continues to scale its Web3 payment infrastructure, with 57Blocks supporting ongoing smart contract upgrades and multi-chain backend optimization.