Piro

A Chainlink CRE workflow polls Polymarket's CLOB API every 60 seconds for the probability of "Will ETH dip to $1,600?", classifies it into Green/Amber/Red tiers, and publishes the tier on-chain to a RiskSignal contract via writeReport. The Uniswap v4 PredictionHook reads this tier in beforeSwap and returns a dynamic fee override (0.30% for Green, 1.00% for Amber) or reverts the swap entirely on Red. A 5-minute staleness window auto-escalates tiers if the CRE workflow stops updating, ensuring fail-safe behavior.

The project has four Solidity contracts built with Foundry, a Chainlink CRE TypeScript workflow, and a zero-dependency frontend dashboard. RiskSignal is an Ownable contract that stores the current risk tier (Green/Amber/Red), a uint64 timestamp, and a uint16 confidence value in a single storage slot. It exposes getEffectiveTier() which handles staleness escalation — if block.timestamp - updatedAt > STALE_WINDOW (300s), the tier is bumped up one level. PredictionHook implements the IHooks interface directly (BaseHook was removed from v4-periphery, so we wrote no-op stubs for all unused callbacks). Only beforeSwap is active — it reads the effective tier from RiskSignal and returns BeforeSwapDelta with lpFeeOverride set via toFee() for Green/Amber, or reverts with SwapBlockedRedTier() for Red. The pool is initialized with DYNAMIC_FEE_FLAG so the hook can override fees. The hook address was mined via CREATE2 through the Deterministic Deployer Proxy (0x4e59...56C) to encode the beforeSwap permission bit in the address. PredictionRouter implements IUnlockCallback for PoolManager.unlock() — it performs the swap, settles input tokens, and takes output tokens, with slippage and deadline checks. RiskSignalReceiver implements Chainlink's IReceiver interface to decode CRE writeReport payloads — it validates the forwarder address and function selector, then forwards setTier(tier, confidence) to RiskSignal. The CRE workflow uses the Chainlink CRE SDK: CronCapability triggers every 60 seconds, HTTPClient fetches from Polymarket's CLOB API with consensus aggregation (median across DON nodes), a classify step maps probability to tier, and EVMClient.writeReport publishes to the receiver on Arbitrum Sepolia. We switched from Polymarket's Gamma API to the CLOB API because Gamma doesn't reliably filter by condition_id. The frontend is a single index.html with inline CSS/JS that reads live on-chain state via raw eth_call RPC (no ethers/viem dependency) and fetches Polymarket probability client-side, auto-refreshing every 30 seconds. All 24 Foundry tests pass, CRE simulation succeeds end-to-end, and we have on-chain transaction proof of swaps under all three tiers on Arbitrum Sepolia.