> For the complete documentation index, see [llms.txt](https://docs.intents.aurora.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.intents.aurora.dev/intents-connect/intents-connect-sdk/examples/hydrex.md). # Hydrex Mint a cbETH/WETH liquidity position on Hydrex (Base) from any chain, in one signature. **A user on any chain opens a concentrated-liquidity position in Hydrex's cbETH/WETH pool on Base.** The position NFT lands in their own wallet. They don't need ETH on Base or a bridge. ## At a glance | | | | ----------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Destination** | Base | | **Protocol** | Hydrex: cbETH/WETH pool `0xB1383DC4…6e97`, position manager (NPM) `0xC63E9672…Ab86` | | **Bridged asset** | Native ETH on Base (`nep141:base.omft.near`) | | **Output** | A position NFT minted to the **user's wallet**. The position holds WETH only | | **Flow / fee** | `bridge-in` · placeholder (EVM default) · fee paid in ETH | | **Source** | [`hydrex/constants.ts`](https://github.com/aurora-is-near/intents-swap-widget/blob/main/apps/intents-connect-demo/src/hydrex/constants.ts) · [`hydrex/plan.ts`](https://github.com/aurora-is-near/intents-swap-widget/blob/main/apps/intents-connect-demo/src/hydrex/plan.ts) | ## What the user does 1. **Connects** an EVM wallet. 2. **Picks** a source token and amount on any supported chain. 3. **Chooses** how to pay: *send from connected wallet*, or deposit to an address or QR code. 4. **Clicks** *Deposit into cbETH/WETH* and **signs** the Intents Connect message. 5. **Approves** the transfer in the wallet (or sends to the QR address). 6. **Sees** the status move to success, and the new position appear in the positions list. There are no range inputs: the dApp picks the price range automatically. ## How it works ```mermaid sequenceDiagram autonumber actor U as User participant D as dApp + SDK participant API as Intents Connect API participant NI as NEAR Intents participant I as Intermediary (Base) participant H as Hydrex D->>H: read pool tick (globalState) D->>API: intermediary + in-flight check D->>API: create execution (steps with {MIN_AMOUNT_OUT}) API-->>D: payload to sign U->>D: sign (erc191) D->>API: submit signature API-->>D: deposit address U->>NI: deposit source token NI->>I: bridge → native ETH on Base I->>H: WETH.deposit · approve · NPM.mint I->>API: fee transfer (ETH) D->>API: poll → SUCCESS H-->>U: position NFT ``` 1. **Pick the range.** The dApp reads the pool's current tick and sets `tickUpper = tick − 2` and `tickLower = tickUpper − 100`. The range sits *below* the price, so the position needs WETH only, and WETH is all the bridge delivers. 2. **Preflight.** The SDK resolves the user's Base intermediary and checks that no other execution is in flight. 3. **Plan.** `buildSteps` runs with `amount = '{MIN_AMOUNT_OUT}'` (placeholder strategy), so one create call is enough. 4. **Create.** The execution is created with three steps. The destination is native ETH, so the destination-token rule doesn't apply. 5. **Sign.** The user signs the payload with their EVM wallet (`erc191`). 6. **Deposit.** After the signature, the deposit address appears. The wallet transfer (or the user's own transfer) sends the source token there. 7. **Bridge.** NEAR Intents / 1Click delivers native ETH to the intermediary on Base. 8. **Execute.** The intermediary runs `WETH.deposit()` (wraps the ETH), `WETH.approve(NPM)` and `NPM.mint(...)`, with `recipient = userAddress`. The service then appends its fee transfer in ETH. 9. **Settle.** The SDK polls until `SUCCESS`. The NFT is already in the user's wallet, and nothing stays in the intermediary. > The demo sets slippage minimums to `0` in `mint`. Set real minimums in production. ## Core code **Recipe:** the three on-chain steps. ```ts const hydrexMintRecipe: Recipe<{ tickLower: string; tickUpper: string }> = { id: 'hydrex-manual-mint', intent: 'hydrex_manual_mint', title: 'Hydrex cbETH/WETH position', flow: 'bridge-in', type: 'evm', destination: { chain: 'base', assetId: 'nep141:base.omft.near' }, // native ETH buildSteps: ({ userAddress, amount }, { tickLower, tickUpper }) => [ { to: WETH, functionSignature: 'deposit()', parameters: [], value: amount }, { to: WETH, functionSignature: 'approve(address,uint256)', parameters: [NPM, amount], value: '0' }, { to: NPM, functionSignature: 'mint((address,address,address,int24,int24,uint256,uint256,uint256,uint256,address,uint256))', parameters: [[CBETH, WETH, ZERO, tickLower, tickUpper, '0', amount, '0', '0', userAddress, deadline]], value: '0', }, ], }; ``` **Plan and run:** ```ts const [, tick] = await base.readContract({ address: POOL, abi: POOL_ABI, functionName: 'globalState' }); const tickUpper = Number(tick) - 2; await exec.run({ recipe: hydrexMintRecipe, params: { tickLower: String(tickUpper - 100), tickUpper: String(tickUpper) }, quote: { originAsset: token.assetId, destinationAsset: 'nep141:base.omft.near', amount: amountAtomic, swapType: 'EXACT_INPUT', slippageTolerance: 100, }, originChain: token.blockchain, originToken: { contractAddress: token.contractAddress, decimals: token.decimals }, depositViaWallet, }); ``` ## Related * [Recipes & fees](/intents-connect/intents-connect-sdk/typescript-sdk/recipes-and-fees.md): placeholders and the placeholder strategy * [Polymarket](/intents-connect/intents-connect-sdk/examples/polymarket.md): the same flow with a token destination --- # Agent Instructions This documentation is published with GitBook. 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