> For the complete documentation index, see [llms.txt](https://docs.warpx.exchange/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.warpx.exchange/for-developers/warpx-v2/periphery.md).

# Periphery

#### WarpRouter02 (Router)

Source: `packages/periphery/contracts/WarpRouter.sol` implementing `IWarpRouter02`.

State: immutable `factory()` and `WETH()` addresses; reverts if `deadline < block.timestamp` on any user-facing method.

**Liquidity Management**

* `addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin, to, deadline)`
  * Approvals required for both tokens to the router.
  * If the pair does not exist, the router creates it on the fly via the factory.
  * Internally balances desired inputs using `WarpLibrary.quote` so slippage bounds (`amountA/BMin`) must be set around expected ratios.
* `addLiquidityETH(token, amountTokenDesired, amountTokenMin, amountETHMin, to, deadline)` (payable)
  * Wraps native ETH into WETH before forwarding into the pair.
  * Refunds surplus ETH to the sender.
* `removeLiquidity(...)` and `removeLiquidityETH(...)`
  * Transfer LP tokens from the caller to the pair, burn them, and distribute assets to `to`.
  * ETH variant unwraps WETH before final transfer.
* Permit variants: `removeLiquidityWithPermit` + `removeLiquidityETHWithPermit` accept EIP-2612 signatures so integrators can batch approve-and-remove in one call.

**Liquidity for Fee-On-Transfer Tokens**

`removeLiquidityETHSupportingFeeOnTransferTokens` and `removeLiquidityETHWithPermitSupportingFeeOnTransferTokens` handle tokens that tax transfers by re-checking router balances instead of the raw burn return values.

**Swap Entry Points**

All swap functions expect an ordered `path` of at least two addresses. The router handles wiring funds between intermediate pairs and enforces min/max slippage via `amountOutMin`/`amountInMax`. Available combinations:

* `swapExactTokensForTokens`
* `swapTokensForExactTokens`
* `swapExactETHForTokens` (payable)
* `swapTokensForExactETH`
* `swapExactTokensForETH`
* `swapETHForExactTokens` (payable)

Fee-on-transfer safe variants (`swapExactTokensForTokensSupportingFeeOnTransferTokens`, `swapExactETHForTokensSupportingFeeOnTransferTokens`, `swapExactTokensForETHSupportingFeeOnTransferTokens`) read the received balance instead of trusting pair outputs.

**Pricing Helpers**

Integrators can quote trades or rebalance liquidity without touching the chain via:

* `quote(amountA, reserveA, reserveB)` – deterministic price quote.
* `getAmountOut(amountIn, reserveIn, reserveOut)` and `getAmountIn(amountOut, reserveIn, reserveOut)` – expose the 0.30% fee curve.
* `getAmountsOut(amountIn, path)` and `getAmountsIn(amountOut, path)` – chain-aware quoting across multiple hops.

These mirror functions in `WarpLibrary` so any SDK code can reuse the same math off-chain.

#### WarpRouter01

`packages/periphery/contracts/WarpRouter01.sol` is a slimmer router that omits fee-on-transfer helpers. Use it only if you require a byte-identical clone of the Uniswap v2 router v1 interface; otherwise `WarpRouter02` (above) is the canonical deployment.

#### WarpMigrator

Source: `packages/periphery/contracts/WarpMigrator.sol`

Single `migrate(token, amountTokenMin, amountETHMin, to, deadline)` entrypoint:

1. Pulls the caller’s entire V1 LP position from the V1 exchange (requires prior approval to the migrator).
2. Removes V1 liquidity and captures the token/ETH amounts.
3. Approves the v2 router for those tokens and adds v2 liquidity via `addLiquidityETH`, respecting the caller’s min amounts.
4. Refunds any excess tokens or ETH back to the caller.

Route bonding-curve graduates or legacy LPs through this migrator to seed v2 pools atomically.