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Oneliq Trade · Feature Deep Dive

Trade: One Interface, Three Settlement Routes

USDC, EURC, and cirBTC across eight testnets from a single form. The route planner builds the step pipeline automatically and shows it before you confirm.

May 28, 2026 6 min read

Trade is Oneliq's interface for swapping, bridging, and spending USDC, EURC, and cirBTC across eight testnets. Enter a source token, a destination token and chain, and an amount. The route planner determines which settlement steps are needed and assembles them into a pipeline. You review the route before anything is signed.

TL;DR
Pick any supported token on any of eight testnets and choose a destination. Trade's route planner builds the steps automatically: a same-chain swap via Circle App Kit, a cross-chain bridge via CCTP V2, a Circle Gateway spend, or a combination. Source your funds from a wallet balance on any chain or from USDC pre-deposited in Circle's GatewayWallet.

What you can trade

Three tokens ship with the built-in token list. Any ERC-20 can be added by contract address.

NetworkBuilt-in tokens
Arc TestnetUSDC (native gas token), EURC, cirBTC
Ethereum SepoliaUSDC, ETH, cirBTC
Base SepoliaUSDC
Avalanche FujiUSDC
Arbitrum SepoliaUSDC
Optimism SepoliaUSDC
Polygon AmoyUSDC
Unichain SepoliaUSDC

On Arc Testnet, USDC is the native gas token: every transaction on the network settles fees in USDC. EURC and cirBTC are ERC-20 contracts deployed alongside it. cirBTC is available in the token picker on Arc and Sepolia. Swap pairs involving cirBTC on Arc route through Uniswap V2, which operates separately from Circle App Kit. Uniswap V2 pool depth for cirBTC pairs on Arc Testnet depends on available liquidity.

Three settlement routes

When you configure a trade, the route planner builds a step pipeline based on the source token, source chain, destination token, and destination chain. Three step types are available, and a single trade can chain more than one.

// Swap
Circle App Kit

USDC and EURC are swapped on Arc Testnet through Circle App Kit. The exchange rate is fetched live from Circle's aggregator at quote time. Not a static formula. Slippage is configurable.

Arc Testnet · USDC / EURC · ~5s
// Bridge
CCTP V2

USDC moves between any two of the eight supported testnets via Circle's Cross-Chain Transfer Protocol. Burned on source, minted 1:1 on destination. No wrapped tokens. Fast or Standard mode.

8 chains · Fast ~20s (fee) · Standard ~13-19 min (free)
// Spend
Circle Gateway

USDC pre-deposited in Circle's GatewayWallet contract is spent cross-chain via an EIP-712 BurnIntent signature. Circle processes the intent and mints USDC at the destination. Supports Unified Balance multi-source.

8 chains · EIP-712 BurnIntent · ~30s

A single trade can combine more than one route. If you hold EURC on Arc and want USDC on Base Sepolia, Trade builds a two-step pipeline: an App Kit swap from EURC to USDC on Arc, followed by a CCTP V2 bridge to Base Sepolia. The route preview panel shows the full pipeline before you confirm anything. A CCTP Fast/Standard toggle appears below the form whenever the route includes a bridge step.

The source picker

Clicking the source button on the Trade page opens a two-column panel: Wallet on the left, Gateway on the right. Each column lists the chains where you hold that kind of USDC balance.

💼 Wallet
Your on-chain USDC (and other tokens) per chain, fetched live from each chain's RPC. Cross-chain trades from a wallet source use CCTP V2 to bridge. Standard CCTP confirmation times apply.
⚡ Gateway
USDC you have pre-deposited into Circle's GatewayWallet contract. Spend cross-chain via EIP-712 BurnIntent. No separate bridge transaction required. Available on all eight supported chains.

When you hold Gateway deposits on two or more chains, a Unified Balance row appears at the top of the Gateway column. Selecting it draws from all funded chains, starting with the largest deposit first, and generates one signed intent per source chain. Circle processes all intents and mints once on the destination chain. See the Unified Balance post for a full walkthrough of Gateway deposits and spend modes.

When the Gateway source is selected, the token picker on the source side is locked to USDC. Gateway deposits are always denominated in USDC; other tokens cannot be sourced from Gateway directly.

Importing custom tokens

In the token search field, paste any ERC-20 contract address starting with 0x. The Trade page queries the on-chain contract for its symbol, name, and decimal count. A confirmation card shows those details along with an Unverified warning before the token is added.

Confirmed imports are saved to your browser's localStorage per chain and persist across sessions. Imported tokens carry an Unverified badge throughout the interface. If a custom token is later added to Oneliq's built-in token list with the same contract address, the imported copy is cleaned up automatically to avoid duplicates.

Walkthrough: 50 EURC on Arc to USDC on Base Sepolia

Starting state: 50 EURC in a wallet on Arc Testnet. Goal: receive USDC on Base Sepolia. This route uses two steps: an App Kit swap on Arc, then a CCTP V2 bridge to Base Sepolia.

1
Open oneliq.xyz/trade and connect your wallet on Arc Testnet.
2
Click the source button. In the Wallet column, select Arc Testnet. Open the token picker and choose EURC. Enter 50 as the amount.
3
In the destination row, select Base Sepolia from the chain dropdown. The token auto-selects USDC (the only token on Base Sepolia).
4
The route preview renders: EURC (Arc) → Swap EURC→USDC on Arc → CCTP Arc→Base → USDC (Base). The CCTP speed toggle appears below the form.
5
Select Fast CCTP mode (~20s, small Circle fee). The quote panel shows the live rate from Circle App Kit, a fee breakdown for both steps, and an estimated time of ~30s.
6
Click Execute. The progress modal opens with two steps listed. Step 1 (Swap): your wallet shows the App Kit swap transaction. Confirm it. EURC is exchanged for USDC on Arc in ~5s.
7
Step 2 (Bridge): your wallet shows the CCTP V2 burn transaction on Arc. Confirm it. Circle's Fast Transfer service processes the attestation in ~20s, then mints USDC on Base Sepolia.
8
USDC arrives on Base Sepolia. The Activity log on the right rail shows both steps as completed. Two wallet confirmations total: one for the swap, one for the bridge.

The same pattern applies in reverse and across other token pairs. USDC on Base Sepolia to EURC on Arc would route as: CCTP bridge Base to Arc, then App Kit swap USDC to EURC on Arc. Trade always moves the cross-chain hop before the swap when the destination token is non-USDC.

One form. Three routes. Eight chains.

Connect a wallet and open Trade to try it. The route planner handles the rest.

Open Trade Read Unified Balance post
Testnet only. No real money.
Everything on Oneliq today runs on testnets. USDC and EURC here are testnet tokens with no monetary value. Never send mainnet assets to a testnet address. Funds sent to a testnet address are unrecoverable.

Oneliq is a non-custodial frontend currently on testnet networks. Nothing here is real money or financial advice. We don't custody funds; you always retain control of your wallet.

© 2026 Oneliq · Built on Arc Testnet
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