Fee Model (EIP-1559)
Basalt implements the EIP-1559 dynamic fee model, where the base fee adjusts automatically based on network demand. This mechanism provides more predictable transaction pricing, eliminates first-price auction inefficiencies, and introduces deflationary pressure through fee burning.
Network Parameters
| Parameter | Mainnet | Testnet | Devnet |
|---|---|---|---|
| Initial Base Fee | 1 gwei | 0.1 gwei | 1 wei |
| Base Fee Change Denominator | 8 | 8 | 8 |
| Elasticity Multiplier | 2 | 2 | 2 |
| Block Gas Limit | 100,000,000 | 100,000,000 | 100,000,000 |
| Target Gas Usage | 50,000,000 | 50,000,000 | 50,000,000 |
The target gas usage is half the block gas limit (determined by the elasticity multiplier of 2). Blocks can temporarily exceed the target up to the full block gas limit, but doing so causes the base fee to increase.
Base Fee Adjustment
The base fee adjusts after every block based on how the actual gas usage compares to the target:
- If gas used exceeds the target, the base fee increases.
- If gas used is below the target, the base fee decreases.
- The maximum change per block is 12.5% (1/8 of the current base fee), governed by the change denominator.
Formula
newBaseFee = baseFee + baseFee * (gasUsed - targetGas) / targetGas / denominator
Where:
baseFeeis the current block's base feegasUsedis the actual gas consumed in the current blocktargetGasis the target gas usage (50,000,000)denominatoris the base fee change denominator (8)
Examples
Given a current base fee of 100 gwei:
| Block Gas Used | Utilization | Base Fee Change | New Base Fee |
|---|---|---|---|
| 50,000,000 | 100% of target | No change | 100 gwei |
| 100,000,000 | 200% of target | +12.5% | 112.5 gwei |
| 75,000,000 | 150% of target | +6.25% | 106.25 gwei |
| 25,000,000 | 50% of target | -6.25% | 93.75 gwei |
| 0 | 0% of target | -12.5% | 87.5 gwei |
Over sustained periods of high demand, the base fee increases exponentially, naturally throttling demand. During low-activity periods, the base fee decreases to its floor.
Transaction Types
Legacy Transactions
Legacy transactions specify a single GasPrice field. The effective gas price is the GasPrice value itself. Legacy transactions are accepted as long as GasPrice >= BaseFee.
EIP-1559 Transactions
EIP-1559 transactions specify two fee parameters:
| Field | Description |
|---|---|
MaxFeePerGas | The absolute maximum the sender is willing to pay per unit of gas |
MaxPriorityFeePerGas | The maximum tip the sender is willing to pay the block proposer |
The effective gas price is calculated as:
effectiveGasPrice = min(MaxFeePerGas, BaseFee + MaxPriorityFeePerGas)
This ensures the sender never pays more than MaxFeePerGas, even if the base fee increases between submission and inclusion.
Fee Distribution
Transaction fees are split into two components:
| Component | Destination | Effect |
|---|---|---|
| Base fee | Burned (destroyed) | Deflationary pressure on BSLT supply |
| Priority fee (tip) | Block proposer | Incentivizes validators to include transactions |
The base fee burn removes BSLT from circulation with every transaction, creating a deflationary mechanism that counterbalances new token issuance from staking rewards. During periods of high network activity, the burn rate can exceed the issuance rate, making BSLT net-deflationary.
Gas Cost Schedule
| Operation | Gas Cost | Description |
|---|---|---|
| Transfer | 21,000 | Native BSLT transfer between accounts |
| Contract Deploy | 500,000 | Deploy compiled contract bytecode |
| Contract Call | 50,000 | Base cost for invoking a contract method |
| DEX Operations | 30,000 -- 120,000 | Variable cost depending on operation complexity |
DEX operation costs vary by type:
- Limit order placement: lower end of the range
- Batch auction settlement: higher end, due to multi-party matching
- Liquidity provision with concentrated ranges: mid-range, includes tick boundary calculations
All gas costs are denominated in gas units. The actual BSLT cost is determined by multiplying the gas consumed by the effective gas price.