← All proposals

LP-052: Price Oracle Aggregation

Abstract

The Lux Price Oracle aggregates prices from multiple on-chain and off-chain sources into a single canonical price per asset pair. Sources include AMM V3 TWAP (LP-041), K-chain oracle feeds (LP-038), and StableSwap virtual prices (LP-042). The aggregator uses a weighted median with freshness scoring to produce manipulation-resistant prices for use by lending protocols, perpetuals, and other DeFi primitives.

Specification

Source Registry

Each price feed aggregates from registered sources:

Source {
    sourceType  uint8       // 0=AMM_TWAP, 1=KCHAIN, 2=STABLESWAP, 3=CUSTOM
    sourceAddr  address     // contract address or feed ID
    weight      uint256     // aggregation weight
    maxStaleness uint256    // max seconds before source is considered stale
}

Aggregation Algorithm

For each price update:

1. Query all registered sources for the current price

2. Discard stale sources (older than maxStaleness)

3. Discard outliers (>3 standard deviations from the unweighted median)

4. Compute weighted median of remaining sources

5. Emit PriceUpdated(feedId, price, timestamp, sourceCount)

Source Types

AMM V3 TWAP: reads the cumulative tick accumulator from V3 pools. Default window: 30 minutes. Resistant to single-block manipulation.

K-chain feed: reads the latest aggregated price from the Oracle VM (LP-038). Sub-second freshness.

StableSwap virtual price: for LP token pricing, reads get_virtual_price() from StableSwap pools (LP-042). Monotonically increasing.

Custom: any contract implementing IOracle.getPrice() returns (uint256 price, uint256 timestamp).

Consumer Interface

interface IPriceOracle {
    function getPrice(bytes32 feedId) external view returns (uint256 price, uint256 timestamp);
    function getPriceTWAP(bytes32 feedId, uint256 window) external view returns (uint256 price);
}

Fallback Chain

If the primary source is stale, the oracle falls through a priority chain:

1. K-chain feed (highest priority, freshest)

2. AMM V3 30-minute TWAP

3. AMM V3 2-hour TWAP (wider window, more resistant)

4. Last known price with staleness flag

Consumers can check timestamp to determine freshness.

Circuit Breaker

If the price changes >20% in a single update, the oracle pauses for 5 minutes and re-queries. This prevents flash crash propagation to dependent protocols.

Security Considerations

1. Multi-source resilience: compromising a single source is insufficient to manipulate the aggregated price (requires >50% of weighted sources).

2. TWAP window: 30-minute TWAP requires sustained manipulation over 30 minutes of on-chain trading, making attacks expensive.

3. Circular dependency: oracle prices must not depend on protocols that themselves depend on the oracle (e.g., oracle using lending pool prices that use the same oracle for liquidations).

Reference

Copyright

Copyright (C) 2024-2026, Lux Partners Limited. All rights reserved.

Licensed under the MIT License.