Overview
LFJ (formerly Trader Joe) implements the Liquidity Book model - a Discrete Liquidity Market Maker (DLMM) that organizes liquidity into discrete price bins. Within a single bin, trades execute at a constant price with zero slippage. Bin sizes are defined by the binStep parameter (in bps), allowing LPs to control their price exposure granularity.
Functions
getLFJPools()
Returns all active LFJ Liquidity Book pairs on Monad.
Returns
| Field | Type | Description |
|---|
pairAddress | Address | LB pair contract address |
tokenX | Address | Token X address |
tokenY | Address | Token Y address |
binStep | number | Bin size in bps (e.g. 20 = 0.2%) |
activeId | number | Current active bin ID |
reserveX | bigint | Total tokenX reserves |
reserveY | bigint | Total tokenY reserves |
feesX | bigint | Accumulated tokenX fees |
feesY | bigint | Accumulated tokenY fees |
import { getLFJPools } from 'rampart-monad'
const pools = await getLFJPools()
for (const pool of pools) {
console.log(`binStep: ${pool.binStep} bps - active bin: ${pool.activeId}`)
}
getLFJPrice()
Returns the spot price for a token pair from the best LFJ pair.
Parameters
| Name | Type | Description |
|---|
tokenA | Address | First token address |
tokenB | Address | Second token address |
number. price of tokenA in units of tokenB from the active bin.
import { getLFJPrice } from 'rampart-monad'
const price = await getLFJPrice(
'0x...', // MON
'0x...' // USDC
)
console.log(`LFJ price: ${price} USDC per MON`)
getLFJPairCount()
Returns the total number of LFJ pairs deployed on Monad.
Returns number. count of all LFJ LB pairs.
import { getLFJPairCount } from 'rampart-monad'
const count = await getLFJPairCount()
console.log(`Total LFJ pairs: ${count}`)
getLFJPairsForTokens()
Finds all LFJ pairs for a specific token combination across all bin steps.
Parameters
| Name | Type | Description |
|---|
tokenA | Address | First token address |
tokenB | Address | Second token address |
LFJPool[]. all pairs matching the token combination, sorted by liquidity.
import { getLFJPairsForTokens } from 'rampart-monad'
// Find all MON/USDC pairs (different bin steps)
const pairs = await getLFJPairsForTokens('0x...', '0x...')
for (const pair of pairs) {
console.log(`Bin step ${pair.binStep}: reserves ${pair.reserveX}/${pair.reserveY}`)
}
LFJ pairs with smaller binStep values (e.g. 1-5 bps) are suitable for stableswap-like pairs. Pairs with larger bin steps (20-100 bps) are better for volatile asset pairs.
Contract Addresses
| Contract | Address |
|---|
| LBFactory | 0xBB4B38A8D3f3afa9Fc6D4d6498b47ADa7D29cDC3 |
