GasFloor White Paper

1. Abstract

GasFloor introduces a novel prediction market design that eliminates the need for external oracles by leveraging Ethereum's native block.basefee opcode (EIP-3198). This enables trustless, atomic resolution for one side of every prediction while maintaining economic security for the other through a bounty-based incentive mechanism.

The protocol implements a peer-to-peer order book model where makers create offers and takers accept the opposite position, allowing for flexible odds and partial fills. Settlement is immediate and verifiable on-chain, providing a transparent and manipulation-resistant prediction market for Ethereum gas prices.

2. Introduction

2.1 The Oracle Problem

Traditional prediction markets rely on external oracles to determine outcomes. This introduces trust assumptions, latency, and potential manipulation vectors. Oracles can be bribed, manipulated, or simply fail to report accurately.

2.2 EIP-3198: BASEFEE Opcode

EIP-3198, implemented in the London hard fork, introduced the BASEFEE opcode that returns the base fee of the current block. This enables smart contracts to atomically verify gas price conditions within the same transaction that settles a prediction.

2.3 Market Opportunity

Ethereum gas prices are notoriously volatile, affected by NFT mints, DeFi activity, and network congestion. Traders, MEV searchers, and protocol operators all have strong interest in hedging or speculating on gas price movements.

3. Core Mechanism

3.1 P2P Order Book Model

Unlike AMM-based prediction markets, GasFloor uses a direct peer-to-peer matching system:

1. Maker creates an offer specifying:
   • Position: YES (gas hits threshold) or NO (gas doesn't hit threshold)
   • Stake amount in ETH
   • Maximum counterparty stake they'll accept
   • Gas price threshold (in wei, but typically set in gwei)
   • Block number deadline
   • Bounty for resolution (minimum 0.003 ETH)
2. Taker(s) accept the opposite position:
   • Multiple takers can partially fill an offer (up to 100 per offer)
   • Only matched portions are at risk
   • Flexible stake amounts within maker's limits

3.2 Implied Odds

The ratio between maker stake and maximum counterparty stake determines the implied probability:

Implied YES Probability = makerStake / (makerStake + maxCounterparty)
Implied NO Probability = maxCounterparty / (makerStake + maxCounterparty)

For example, if a YES maker stakes 0.7 ETH and accepts up to 0.3 ETH from takers, the implied odds are 70% YES / 30% NO.

4. Smart Contract Architecture

4.1 Offer Structure

struct Offer {
    address maker;           // Offer creator
    bool makerBetsYes;       // true = maker bets YES
    bool resolved;           // Has offer been resolved
    bool outcome;            // true = YES won, false = NO won
    uint256 makerStake;      // Maker's ETH stake
    uint256 maxCounterparty; // Max ETH from takers
    uint256 totalTakerStake; // Sum of all taker deposits
    uint256 threshold;       // Base fee threshold (wei)
    uint256 deadline;        // Block number deadline
    uint256 bounty;          // Resolver reward
}

4.2 Core Functions

4.3 Events

event OfferCreated(uint256 indexed offerId, address indexed maker, ...);
event OfferTaken(uint256 indexed offerId, address indexed taker, uint256 amount);
event OfferResolved(uint256 indexed offerId, bool outcome, address resolver);
event OfferCancelled(uint256 indexed offerId);
event Claimed(uint256 indexed offerId, address indexed claimer, uint256 amount);
event BountyWithdrawn(uint256 indexed offerId, address indexed resolver, uint256 amount);

5. Resolution Mechanics

5.1 Trustless YES Resolution

The resolveYes() function can be called by anyone when the current block's base fee meets or exceeds the threshold:

function resolveYes(uint256 offerId) external {
    Offer storage offer = offers[offerId];
    require(!offer.resolved, "Already resolved");
    require(block.basefee >= offer.threshold, "Threshold not met");

    offer.resolved = true;
    offer.outcome = true;
    resolver[offerId] = msg.sender;

    emit OfferResolved(offerId, true, msg.sender);
}

5.2 Economic Security for NO Resolution

For NO outcomes, we cannot prove a negative trustlessly (we can't prove gas will never hit the threshold). Instead, we use economic incentives:

function resolveNo(uint256 offerId) external {
    Offer storage offer = offers[offerId];
    require(!offer.resolved, "Already resolved");
    require(block.number > offer.deadline, "Deadline not passed");

    offer.resolved = true;
    offer.outcome = false;
    resolver[offerId] = msg.sender;

    emit OfferResolved(offerId, false, msg.sender);
}

The bounty (minimum 0.003 ETH, ~$10) incentivizes anyone to call resolveNo() after the deadline. This is a simple, gas-efficient operation that anyone monitoring the blockchain can execute for profit.

5.3 Payout Calculation

Winners receive their stake back plus a proportional share of the loser's stake:

// If YES wins:
makerPayout = (makerStake * totalPool) / winnerStake
takerPayout = (takerStake * totalPool) / winnerStake

// Unmatched maker stake always returned
unmatchedReturn = makerStake - matchedMakerStake

6. Security Considerations

6.1 Implemented Protections

• Reentrancy Protection: Checks-Effects-Interactions (CEI) pattern throughout
• Integer Overflow: Solidity 0.8+ built-in overflow checks
• Double Claim Prevention: State zeroing after payout
• Griefing Prevention: Bounded arrays (max 100 takers), minimum stakes
• Resolution Blocking Prevention: Pull-based bounty withdrawals

6.2 Attack Vectors Considered

7. Protocol Parameters

8. Economic Analysis

8.1 Market Efficiency

The P2P model allows markets to form at any odds, rather than being constrained by AMM curves. This enables more accurate price discovery for gas predictions.

8.2 Resolver Incentives

Resolvers are incentivized by bounties. For YES resolution, they must time their transaction for a block with sufficient base fee. For NO resolution, they simply need to monitor the blockchain and act after deadlines pass.

8.3 Arbitrage Opportunities

If markets misprice gas volatility, arbitrageurs can profit by taking positions and hedging with gas futures or other mechanisms, bringing prices toward efficiency.