Blockchain Integration
Ukiyo executes on Arbitrum One and anchors settlement and governance-critical roots to Ethereum L1.
Network roles
| Network | Role |
|---|---|
| Arbitrum One | SPOOL contracts, policy engine, score publication, agent execution |
| Ethereum L1 | Settlement root, Merkle anchors, timelocked governance |
| Base (optional) | Consumer surfaces — account for bridge hops explicitly |
Finality levels on Arbitrum
latest— soft finality (sequencer promise, reversible).safe— batch posted; parent-chain safe.- Hard L1 finality — after optimistic challenge window (~7 days for native withdrawals).
Choose confirmation level per action class: risk-reducing pauses can use faster confirmation; large L1 settlements must disclose challenge delay.
Stylus split
Compute-heavy credit logic can run as Rust/WASM Stylus contracts beside Solidity. Keep order NFT, spool accounting, and access control in Solidity; put advance preview, aggregation, and heavy verification paths in Stylus when gas warrants it.
Timeboost (optional)
Express-lane inclusion can prioritize latency-sensitive pauses/reprices. Treat Timeboost as an optimization, not a security boundary — policy still enforces allowlists.
Cross-chain advances (e.g. fund on Arbitrum, receive on Base) require explicit bridge timing in repayment and risk disclosure. Do not assume atomicity across L2s.