# ✨ Implement Dynamic Fee Adjustment Mechanism
## Overview
Implements a dynamic fee adjustment mechanism, replacing the constant
fee multiplier with an adaptive multiplier that responds to network
congestion, following Moonbeam's pattern.
## Changes
- Replaces `ConstFeeMultiplier` with `TargetedFeeAdjustment` across all
runtime configurations (mainnet, stagenet, testnet)
- Implements an EIP-1559-like slow-adjusting fee mechanism that prevents
DoS attacks by adjusting fees based on block fullness
- **Configurable Parameters**:
- Target block fullness: 35%
- Adjustment variable: 4/1000 (responds in ~1 hour at extreme
congestion)
- Two modes:
- `SlowAdjustingFeeUpdate` for mainnet and testnet.
- `FastAdjustingFeeUpdate` for stagenet.
- Adds tests coverage for different fee scenarios
## Technical Details
The fee adjustment algorithm works as follows:
```
diff = (previous_block_weight - target) / maximum_block_weight
next_multiplier = prev_multiplier * (1 + (v * diff) + ((v * diff)^2 / 2))
assert(next_multiplier > min)
```
**Where:**
- `v` = AdjustmentVariable
- `target` = TargetBlockFullness
- `min` = MinimumMultiplier
`SlowAdjustingFeeUpdate` sets a minimum multiplier of `1x` for a
conservative fee adjustment, while `FastAdjustingFeeUpdate` sets it to
`0.1x`, which is mainly used for dev networks / testing.
