Smart contracts

AchSwap on Arc Mainnet has four groups of contracts:

• its own V2 and V3 liquidity;
• the swap executor and its adapters, which execute every AchSwap route;
• the gasless executor;
• a helper for paying with native USDC.

Every live AchSwap contract is source-verified on ArcScan except the Virtuals adapter (adapter 6), which is live but not yet verified (checked 10 October 2026). Source verification is not an audit: see security. Addresses are in the address reference.

AchSwap V2 and V3

The V2 factory creates constant-product pairs, and the V2 router handles swaps and liquidity. LP shares are fungible tokens.

The V3 factory creates concentrated-liquidity pools with fee tiers of 0.01%, 0.05%, 0.3%, 1% and 10%. The other V3 contracts:

• The SwapRouter executes swaps. It is a legacy SwapRouter that requires a deadline, not SwapRouter02.
• The QuoterV2 returns quotes through calls.
• The NonfungiblePositionManager owns positions as NFTs.
• The migrator moves V2 positions to V3.

AchSwap's own V4 contracts are not deployed on Arc Mainnet. Uniswap V4 is an independent protocol that AchSwap routes through.

Swap execution

AchRouteExecutor executes every AchSwap route in one transaction:

• It takes an exact-input plan of up to 8 branches and 32 steps, with up to 8 steps per branch. Each step names an adapter and a pool.
• It moves tokens straight between pools through six execution adapters, without any third-party router:
  • native USDC conversion;
  • V2 pairs;
  • V3 and Slipstream pools;
  • Uniswap V4 pools, including hooked pools;
  • Lunya pools;
  • Virtuals launch curves.
• It measures what every step actually produced and charges 0.25% once, on the final output. The fee goes straight to the AchSwap treasury Safe; there is no fee vault.
• It pays the recipient and requires the recipient's real balance increase to reach their minimum. Otherwise the whole transaction reverts.
• It refunds this call's residuals and holds nothing between transactions.

The executor does not discover routes. AchSwap's routing engine computes them, and anyone can encode one. The interface, route encoding, adapter payloads and safety rules are on the swap execution page.

Gasless

AchSponsoredExecutorV3 runs gasless swaps:

1. The user signs one Permit2 witness that binds the whole swap.
2. An allowlisted relayer submits it and pays the gas.
3. The executor pulls the exact input through Permit2 and calls an allowlisted target (KyberSwap, LI.FI or AchRouteExecutor) with the signed calldata.
4. The executor checks the minimum against the user's actual balance increase.

Inputs are limited to USDC, EURC and cirBTC. Output tokens are not restricted. See gasless architecture.

Native USDC helper

AchArcNativeUsdcAdapter adds liquidity to AchSwap's own V2 and V3 contracts, and swaps on them, with USDC paid from the native balance. This saves the separate approval transaction.

Arc USDC

The ERC-20 USDC at 0x3600000000000000000000000000000000000000 has 6 decimals. Native USDC uses 18-decimal units and is the same balance. AchRouteExecutor accepts and pays either form: adapter 1 converts between them at exactly 10¹², and the executor treats both as one balance. Pools and ordinary routers use the ERC-20 form. The V2/V3 routers' WETH placeholder is an unsupported contract, so their ETH-path methods are not used on Arc.

What the owners can and cannot do

Contract	The owner can	The owner cannot
AchRouteExecutor	Pause execution. Disable an adapter. Add an adapter after a 2-day delay. Lower the fee at once, or raise it after a 2-day delay, up to 1%. Change the fee recipient after a 2-day delay, and only if the new recipient accepts.	Move user funds. Apply a new fee to a plan built under the old one (the plan carries the fee version). Point an existing adapter id at different code. Renounce ownership.
Execution adapters	Deny a Uniswap V4 hook (adapter 4 only).	Change factories, fees, callback selectors or the PoolManager. Call an adapter at all: only the executor can.
AchSponsoredExecutorV3	Curate the input tokens, targets, spenders and relayers. Pause.	Change a signed swap, or pull more than the signed amount.

Verification

All live contracts except the Virtuals adapter (adapter 6) are verified on ArcScan with exact source matches and constructor arguments; adapter 6 is live but its source is not yet verified (checked 10 October 2026). The executor and its adapters were compiled with solc 0.8.24 (via-IR, optimizer 200 runs, EVM cancun). Their deployed runtime bytecode matches the verified sources.

See fees and smart routing.