FEEIn the programBit 1

Dynamic fees

The fee rises with how far a swap pushes the price. Pushing it back is free.

Add to the builder All Hook Blocks

Where it runs

Fee

Sets or adds to what the swap pays.

Status on reel

In the program

In the reel program: bit 1 of PoolParams.blocks, frozen at PoolInit (PROGRAM.md §5).

Set by

You, at launch

Frozen in PoolParams at PoolInit; nobody can change it after.

What it does

A reference price trails the market. A swap moving price away from it pays an extra LP fee that grows with the square of the distance, averaged over the swap's own path so splitting a trade saves nothing, up to a ceiling. Moving back toward the reference is free. Without a counted move the reference steps toward the price, then joins it after a reset.

How it works on reel

dyn_ref steps every dyn_window_secs keeping dyn_carry_bps of the gap (at most 64 steps) and joins the price after dyn_reset_secs with no counted move. Moving away pays min(span, sens·(d0² + d0·d1 + d1²)/3,300) pips, d the bps distance from the reference (capped at 20,000), d0 = 0 when the swap crosses it. A move counts when |Δp| ≥ dyn_move_bps and X ≥ dyn_ref_liq (opening depth ÷ divisor). Exact-out swaps pay the span. The protocol share applies above the base fee.

Settings · 7

Setting	Min	Default	Max	What it does
Fee ceiling `dyn_max_pips`	See rule	2.3%	60%	The most a swap pays in base plus dynamic fee. The default is the base fee + 20,000.From the base fee + 1 up to 600,000; it includes the base fee.
Sensitivity `dyn_sens`	1	5	10	How fast the fee climbs: a swap leaving the reference pays sens·d²/3,300 pips for a move of d bps, up to the ceiling.
Step every `dyn_window_secs`	12 s	30 s	5 min	Each window, the reference keeps the carry share of its gap to the price.
Reset after `dyn_reset_secs`	30 s	2 min	30 min	With no counted move for this long, the reference joins the price.At least twice the step.
Gap kept per step `dyn_carry_bps`	0%	75%	95%	Share of the gap between reference and price kept at each step.
Counted move `dyn_move_bps`	0.5%	2%	20%	A move counts when the price moves at least this far and the swap is at least the reference liquidity.
Liquidity divisor `dyn_divisor`	2	100	10,000	Reference liquidity = the pool's quote depth at open ÷ this. A push with no size behind it doesn't raise the next buyer's fee.

Fees and who's paid

Paid to

LPs, after reel's share of the part above the base fee.

Protocol share

reel's protocol share s (20–50%, fixed at launch) comes off each charge first.

Requires and can't be combined with

Requires

No other block.

Can't be combined with

Storm Fee

Worked example

Base 0.3%, ceiling 2.3%, sensitivity 5: a 1 SOL buy that moves price 10% from the reference pays 5·1,000²/3,300 ≈ 1,515 pips, about 0.15% above the base fee: 0.0015 SOL, of which 0.0003 SOL goes to reel at a 20% share.