SmoothYield — Add BTC Staking to Any TradFi App with Starkzap

SmoothYield is an open-source reference app that shows web2 developers how to add passive BTC yield to a traditional finance (TradFi) mobile app — no seed phrases, no gas fees, no blockchain UX. The entire crypto layer is powered by Starkzap, the official Starknet developer toolkit.

TL;DR — Your users sign in with Google. Behind the scenes, Starkzap creates an invisible Starknet wallet and stakes LBTC for ~3.3% APY. All transactions are gasless (sponsored by the AVNU paymaster). Your users never see a wallet address, sign a transaction, or pay gas. They just see "Earning 3.33% APY on BTC".

Why Add Crypto Rails to a TradFi App?

Traditional finance apps (stock brokers, neobanks, portfolio trackers) can unlock new revenue streams and user retention by offering passive crypto yield — without rebuilding the app as a "crypto app". Here is what Starkzap enables:

Benefit	How It Works
No wallet UX	Privy creates invisible embedded wallets. Users sign in with Google/email — no MetaMask, no seed phrases.
No gas fees	The AVNU paymaster sponsors every transaction. Your users never need to hold ETH or STRK for gas.
Real BTC yield	LBTC staking on Starknet earns ~3.3% APY through native delegation to Starknet validators.
4 npm packages	`starkzap` + `@privy-io/expo` + `@privy-io/node` + `starknet`. That's the full crypto stack.
Backend-only signing	All transaction signing happens on your server. The mobile app never touches private keys.

Your users see a TradFi app with stocks, cash, and a "BTC Yield" tab. Behind the scenes, Starkzap handles wallets, staking, and gas — all in a few function calls.

Architecture Overview

┌──────────────────────────────────────────────────────────────────┐
│                         Mobile App (Expo)                        │
│                                                                  │
│   PrivyProvider → Google OAuth → AuthContext (sessionId)         │
│   Screens: Stocks | Crypto | Portfolio | Profile                 │
│   YieldScreen: "Stake BTC now" button                           │
│                                                                  │
│   No wallet addresses shown.  No gas prompts.  No crypto UX.    │
└─────────────────────────────┬────────────────────────────────────┘
                              │  REST API (x-session-id)
                              ▼
┌──────────────────────────────────────────────────────────────────┐
│                       Backend (Express)                          │
│                                                                  │
│   Auth:  Privy token verification → session                      │
│   Wallet: Privy server SDK → create Starknet wallet              │
│   Stake: Starkzap Staking → delegate LBTC to validator pool      │
│   Gas:   AVNU Paymaster → all transactions sponsored             │
│   Sign:  Privy rawSign → server-side, no user interaction        │
│                                                                  │
│   Key service: backend/src/services/starkzap.ts                  │
└─────────────────────────────┬────────────────────────────────────┘
                              │  Starkzap SDK + Paymaster
                              ▼
┌──────────────────────────────────────────────────────────────────┐
│                         Starknet                                 │
│                                                                  │
│   Account deployment (sponsored)                                 │
│   ERC-20 token transfers (LBTC)                                  │
│   Native staking (LBTC → validator pool → yield)                │
└──────────────────────────────────────────────────────────────────┘

Starkzap Modules Used

SmoothYield imports these modules from the starkzap npm package:

Module	Purpose	Where Used
`StarkZap` / `StarkSDK`	Main SDK class — initializes RPC, paymaster, network config	`backend/src/services/starkzap.ts`
`OnboardStrategy`	Enum for wallet onboarding strategies (`Privy`, `Argent`, etc.)	`mobile/src/starknet/useStarknetWallet.ts`
`accountPresets`	Preconfigured account types (e.g. `argentXV050`)	`mobile/src/starknet/useStarknetWallet.ts`
`WalletInterface`	TypeScript type for the onboarded wallet object	`mobile/src/starknet/useStarknetWallet.ts`
`mainnetTokens` / `sepoliaTokens`	Token presets (USDC, LBTC addresses and decimals)	`backend/src/services/starkzap.ts`
`Staking`	Staking class — `fromPool`, `populateEnter`, `populateAdd`, `populateExitIntent`, `populateExit`, `getStakerPools`, `isMember`	`backend/src/adapters/staking.ts`
`Amount`	Token amount helper — `fromRaw`, `toBase`, `toUnit`	`backend/src/adapters/staking.ts`
`ChainId`	Chain identifier enum (`MAINNET`, `SEPOLIA`)	`backend/src/adapters/staking.ts`, `starkzap.ts`
`getStakingPreset`	Returns staking configuration for a given chain	`backend/src/adapters/staking.ts`, `starkzap.ts`
`mainnetValidators` / `sepoliaValidators`	Validator registry for LBTC pool discovery	`backend/src/services/starkzap.ts`

The Starkzap SDK also handles:

Paymaster integration — pass your AVNU API key and all wallet.execute() calls become gasless.
Privy onboarding — sdk.onboard({ strategy: "privy", ... }) connects a Privy-managed wallet to Starkzap in one call.
Account deployment — wallet.deploy({ feeMode: "sponsored" }) deploys the account contract on-chain, gas-free.

Step-by-Step: How Starkzap Is Integrated

This section walks through every integration point so you can replicate it in your own app. Each step includes the actual code from this repository.

Step 1: Install Starkzap

Add the starkzap package to both your backend and frontend:

# Backend
cd backend
npm install starkzap starknet @privy-io/node

# Mobile / Frontend
cd mobile
npm install starkzap @privy-io/expo

That's it. No complex blockchain toolchains, no Solidity compilers, no ABIs. Starkzap is a pure JavaScript/TypeScript SDK.

Step 2: Get Your API Keys

You need three services — all have free tiers:

Service	What It Does	Where to Get It
Privy	User auth + embedded wallets	dashboard.privy.io
AVNU	Paymaster (gas sponsorship)	portal.avnu.fi
Alchemy (optional)	Starknet RPC node	dashboard.alchemy.com

Set them in your backend .env:

PRIVY_APP_ID=your-privy-app-id
PRIVY_APP_SECRET=your-privy-app-secret
AVNU_PAYMASTER_API_KEY=your-avnu-key
ALCHEMY_STARKNET_API_KEY=your-alchemy-key   # optional
STARKNET_NETWORK=sepolia                     # or mainnet

Step 3: Initialize the Starkzap SDK

The SDK is initialized once and reused. The key configuration is the paymaster — this is what makes every transaction gasless.

import("starkzap").then((starkzap) => {
  const sdk = new starkzap.StarkZap({
    network: "sepolia",                    // or "mainnet"
    rpcUrl: "https://starknet-sepolia.g.alchemy.com/v2/YOUR_KEY",

    // This is the magic: AVNU paymaster makes all txs gasless
    paymaster: {
      nodeUrl: "https://sepolia.paymaster.avnu.fi",
      headers: { "x-paymaster-api-key": "YOUR_AVNU_KEY" },
    },
  });
});

Docs: Starkzap Paymasters and AVNU Paymaster Integration

In SmoothYield, this lives in backend/src/services/starkzap.ts — the getSdk() function lazily initializes it:

async function getSdk() {
  if (_sdk) return _sdk;
  const starkzap = await import("starkzap");
  const Cls = starkzap.StarkSDK ?? starkzap.StarkZap;
  // ... RPC URL resolution ...

  const paymaster =
    config.avnuPaymasterApiKey
      ? {
          nodeUrl:
            config.network === "sepolia"
              ? "https://sepolia.paymaster.avnu.fi"
              : "https://starknet.paymaster.avnu.fi",
          headers: { "x-paymaster-api-key": config.avnuPaymasterApiKey },
        }
      : undefined;

  _sdk = new Cls({
    ...sdkConfig,
    ...(paymaster && { paymaster }),
  });
  return _sdk;
}

Step 4: Create Invisible Wallets with Privy

When a user signs in with Google, your backend creates a Starknet wallet for them using Privy's server SDK. The user never sees this wallet.

import { PrivyClient } from "@privy-io/node";

const privy = new PrivyClient({
  appId: "your-privy-app-id",
  appSecret: "your-privy-app-secret",
});

// One line to create a Starknet wallet
const wallet = await privy.wallets().create({
  chain_type: "starknet",
});

// wallet.id       → "wallet_abc123"  (used for signing)
// wallet.address  → "0x04a3..."      (Starknet address)
// wallet.public_key → "0x02b1..."    (needed for Starkzap onboard)

Docs: Starkzap Privy Integration

In SmoothYield, this lives in backend/src/services/privyWallet.ts:

export async function createStarknetWallet(_privyUserId: string): Promise<PrivyWallet> {
  const privy = getPrivyClient();
  const wallet = await privy.wallets().create({
    chain_type: "starknet",
  });
  const address = normalizeStarknetAddress(wallet.address);
  return {
    id: wallet.id,
    address,
    public_key: wallet.public_key ?? "",
    chain_type: wallet.chain_type,
  };
}

Step 5: Onboard a Wallet into Starkzap

This is the central integration point. sdk.onboard() connects the Privy wallet to Starkzap so it can execute transactions (staking, transfers) — all server-side.

const wallet = await sdk.onboard({
  strategy: "privy",
  privy: {
    resolve: async () => ({
      walletId: "wallet_abc123",              // from Privy
      publicKey: "0x02b1...",                  // from Privy
      serverUrl: "https://your-api.com/api/wallet/sign",  // your sign endpoint
    }),
  },
  deploy: "never",          // deploy on first real tx, not eagerly
  feeMode: "sponsored",     // gasless via paymaster
});

// wallet can now execute(), balanceOf(), deploy(), etc.

The serverUrl points to your backend endpoint that signs transaction hashes using Privy's rawSign:

// POST /api/wallet/sign — Starkzap calls this automatically
const result = await privy.wallets().rawSign(walletId, {
  params: { hash: "0x..." },
});
return { signature: result.signature };

Docs: Starkzap Connecting Wallets and Privy Integration

In SmoothYield, the onboard function is in backend/src/services/starkzap.ts:

export const onboardPrivyWallet = async (
  _privyUserId: string,
  privyWalletId: string,
  publicKey: string,
  signEndpointUrl: string
) => {
  if (!config.avnuPaymasterApiKey) {
    throw new Error(
      "AVNU_PAYMASTER_API_KEY is required for gasfree (sponsored) deploy and execute. Set it in backend .env. See https://docs.starknet.io/build/starkzap/paymasters"
    );
  }
  const sdk = await getSdk();
  if (!sdk?.onboard) throw new Error("Starkzap SDK onboard unavailable");

  const result = await sdk.onboard({
    strategy: "privy",
    privy: {
      resolve: async () => ({
        walletId: privyWalletId,
        publicKey,
        serverUrl: signEndpointUrl,
      }),
    },
    deploy: "never",
    feeMode: "sponsored",
  });
  return result?.wallet ?? result;
};

Step 6: Read Token Balances

Starkzap provides token presets with correct addresses and decimals for each network. Use them to read balances:

const starkzap = await import("starkzap");

// Get token presets for the current network
const tokens = starkzap.sepoliaTokens; // or mainnetTokens

// tokens.USDC  → { address: "0x...", decimals: 6, symbol: "USDC" }
// tokens.LBTC  → { address: "0x...", decimals: 8, symbol: "LBTC" }

// Read balance using the onboarded wallet
const usdcBalance = await wallet.balanceOf(tokens.USDC);
console.log(usdcBalance.toBase());  // raw amount (e.g. "1000000" = 1 USDC)

In SmoothYield, getTokenAddresses() resolves tokens from Starkzap presets and supports optional address overrides via environment variables:

export const getTokenAddresses = async (): Promise<{
  usdc: Token;
  usdcBridged: Token | null;
  lbtc: Token;
}> => {
  const preset = await getPresetTokens();
  const usdc = config.usdcTokenAddress
    ? tokenOverride(config.usdcTokenAddress, preset.USDC)
    : preset.USDC;
  const usdcBridged =
    "USDC_E" in preset && preset.USDC_E && !config.usdcTokenAddress
      ? preset.USDC_E
      : null;
  const lbtc = config.lbtcTokenAddress
    ? tokenOverride(config.lbtcTokenAddress, preset.LBTC)
    : preset.LBTC;
  return { usdc, usdcBridged, lbtc };
};

Step 7: Stake LBTC for Yield

This is where the real magic happens. Starkzap's Staking module lets you stake LBTC in a validator's delegation pool to earn yield — all in a few lines.

const starkzap = await import("starkzap");
const { Staking, Amount, ChainId, getStakingPreset } = starkzap;

// 1. Get the staking configuration for this network
const chainId = ChainId.SEPOLIA;   // or ChainId.MAINNET
const stakingConfig = getStakingPreset(chainId);

// 2. Connect to a validator's LBTC staking pool
const staking = await Staking.fromPool(poolAddress, provider, stakingConfig);

// 3. Build the staking calls
const amount = Amount.fromRaw("100000000", 8, "LBTC");  // 1 LBTC
const isMember = await staking.isMember(wallet);

const calls = isMember
  ? staking.populateAdd(walletAddress, amount)      // already staking → add more
  : staking.populateEnter(walletAddress, amount);   // first time → enter pool

// 4. Execute gaslessly
const tx = await wallet.execute(calls, { feeMode: "sponsored" });

Pool discovery is automatic — Starkzap provides a validator registry:

const validators = starkzap.sepoliaValidators;   // or mainnetValidators
for (const validator of Object.values(validators)) {
  const pools = await Staking.getStakerPools(provider, validator.stakerAddress, stakingConfig);
  const lbtcPool = pools.find(p => p.token.symbol === "LBTC");
  if (lbtcPool) {
    // lbtcPool.poolContract is your pool address
  }
}

In SmoothYield, the full staking flow is in backend/src/adapters/staking.ts:

  // Native staking via Starkzap: build approve + enter/add calls, normalize for paymaster, then execute
  const starkzap = await import("starkzap");
  const { Staking, Amount, ChainId, getStakingPreset } = starkzap;
  const provider = getProvider();
  const chainId = config.network === "sepolia" ? ChainId.SEPOLIA : ChainId.MAINNET;
  const stakingConfig = getStakingPreset(chainId);
  // ...
  const staking = await Staking.fromPool(poolAddress as any, provider as any, stakingConfig);
  // ...
  const rawCalls = isMember
    ? staking.populateAdd(walletAddress, amountObj)
    : staking.populateEnter(walletAddress, amountObj);

  const tx = await sendSponsoredTx(wallet, rawCalls);
  // ...

Step 8: Unstake and Withdraw

Starknet staking has a two-phase exit: first declare intent, then withdraw after the cooldown.

// Phase 1: Exit intent — "I want to unstake X LBTC"
const amount = Amount.fromRaw("100000000", 8, "LBTC");
const exitIntentCall = staking.populateExitIntent(amount);
await wallet.execute([exitIntentCall], { feeMode: "sponsored" });

// Phase 2: Exit — after cooldown period passes
const exitCall = staking.populateExit(walletAddress);
await wallet.execute([exitCall], { feeMode: "sponsored" });

In SmoothYield, these are the POST /api/yield/unstake and POST /api/yield/exit endpoints in backend/src/adapters/staking.ts.

The Paymaster: Gasless Transactions

The AVNU paymaster is what makes this app feel like a traditional fintech app. Without it, every transaction would require the user to hold STRK or ETH for gas fees — a dealbreaker for TradFi users.

How it works:

You get an API key from portal.avnu.fi
You pass it to the Starkzap SDK at initialization
Every wallet.execute(calls, { feeMode: "sponsored" }) call is gasless
AVNU pays the gas. You can set up billing with them for production.

What's sponsored:

Account deployment (wallet.deploy({ feeMode: "sponsored" }))
Staking deposits and withdrawals
Any multicall transaction

Configuration in SmoothYield:

Network	Paymaster URL
Sepolia (testnet)	`https://sepolia.paymaster.avnu.fi`
Mainnet	`https://starknet.paymaster.avnu.fi`

Docs: Starkzap Paymasters · AVNU Paymaster Integration

Project Structure

smoothyield/
├── backend/                          # Express API server
│   ├── src/
│   │   ├── services/
│   │   │   ├── starkzap.ts          # Starkzap SDK init, onboard, balances, sponsored tx
│   │   │   ├── privyWallet.ts       # Privy wallet creation + rawSign
│   │   │   └── privy.ts             # Privy token verification
│   │   ├── adapters/
│   │   │   └── staking.ts           # Starkzap Staking: stake, unstake, exit
│   │   ├── routes/index.ts          # All API endpoints
│   │   ├── config.ts                # Environment configuration
│   │   ├── db.ts                    # SQLite (sessions, wallets, yield)
│   │   └── middleware.ts            # Session auth middleware
│   ├── .env.example
│   └── package.json
│
├── mobile/                           # Expo React Native app
│   ├── app/
│   │   ├── _layout.tsx              # PrivyProvider + AuthProvider
│   │   └── (tabs)/                  # Tab navigation (stocks, crypto, portfolio, profile)
│   ├── src/
│   │   ├── context/AuthContext.tsx   # Privy auth → backend session
│   │   ├── screens/
│   │   │   ├── YieldScreen.tsx      # BTC staking UI
│   │   │   ├── CryptoScreen.tsx     # Crypto balances + markets
│   │   │   ├── PortfolioScreen.tsx  # TradFi + crypto holdings
│   │   │   └── LoginScreen.tsx      # Google OAuth login
│   │   ├── starknet/
│   │   │   ├── useStarknetWallet.ts # Client-side Starkzap onboard hook
│   │   │   └── walletClient.ts      # Wallet fetch + Privy resolve builder
│   │   └── components/              # UI components (StakingCard, BalanceCard, etc.)
│   ├── .env.example
│   └── package.json
│
├── types/                            # Shared TypeScript types
└── package.json                      # Workspace root

Quick Start

1. Backend

cd backend
cp .env.example .env
# Edit .env — set PRIVY_APP_ID, PRIVY_APP_SECRET, AVNU_PAYMASTER_API_KEY
npm install
npm run dev

2. Mobile

cd mobile
cp .env.example .env
# Edit .env — set EXPO_PUBLIC_PRIVY_APP_ID and EXPO_PUBLIC_API_URL
npm install
npm run start

On a physical device: use your machine's LAN IP for EXPO_PUBLIC_API_URL (e.g. http://192.168.1.5:3000) since localhost on the device refers to the device itself.

3. Dev Mode

Set DEV_MODE=true in backend/.env to mock auth/staking for local testing without real credentials. The full yield flow can be tested end-to-end with mock transactions.

Environment Variables

Backend (`backend/.env`)

Variable	Required	Description
`PRIVY_APP_ID`	Yes	From dashboard.privy.io
`PRIVY_APP_SECRET`	Yes	From Privy dashboard
`AVNU_PAYMASTER_API_KEY`	Yes	From portal.avnu.fi — enables gasless transactions
`ALCHEMY_STARKNET_API_KEY`	No	Starknet RPC via Alchemy (recommended for production)
`STARKNET_RPC_URL`	No	Override RPC URL entirely
`STARKNET_NETWORK`	No	`sepolia` (default) or `mainnet`
`DEV_MODE`	No	`true` for mock mode
`BTC_STAKING_APY`	No	Override displayed APY (default: 3.33)
`PORT`	No	Server port (default: 3000)

Mobile (`mobile/.env`)

Variable	Required	Description
`EXPO_PUBLIC_PRIVY_APP_ID`	Yes	Same Privy App ID
`EXPO_PUBLIC_API_URL`	Yes	Backend URL (e.g. `http://localhost:3000`)

API Reference

Method	Endpoint	Auth	Description
`GET`	`/health`	Public	Health check
`GET`	`/api/market-data`	Public	Stock + crypto market prices
`POST`	`/api/auth/session`	Public	Exchange Privy token for session
`POST`	`/api/wallet/starknet`	Bearer	Get/create Starkzap-compatible wallet
`POST`	`/api/wallet/init`	Session	Initialize wallet + optional deploy
`POST`	`/api/wallet/sign`	Key/Bearer	Sign transaction hash (Starkzap callback)
`GET`	`/api/wallet/address`	Session	Get wallet address
`POST`	`/api/wallet/deploy`	Session	Deploy account on-chain (sponsored)
`GET`	`/api/portfolio`	Session	TradFi + crypto balances + yield state
`POST`	`/api/yield/stake`	Session	Stake LBTC for yield
`POST`	`/api/yield/unstake`	Session	Exit intent (begin unstaking)
`POST`	`/api/yield/exit`	Session	Finalize withdrawal after cooldown
`GET`	`/api/tx/:hash`	Session	Check transaction status

End-to-End Yield Flow

Here is what happens when a user taps "Stake BTC now" in the app:

User taps "Stake BTC now"
        │
        ▼
1. POST /api/wallet/init
   └─ Backend creates Privy wallet (if needed)
   └─ Calls sdk.onboard({ strategy: "privy" })
   └─ Optionally deploys account (sponsored)
        │
        ▼
2. POST /api/yield/stake { amountLbtc: "100000000" }
   └─ Backend onboards wallet via Starkzap
   └─ Resolves LBTC pool via Starkzap validators
   └─ Calls Staking.fromPool() → staking.populateEnter()
   └─ Executes via wallet.execute(calls, { feeMode: "sponsored" })
   └─ Starkzap calls POST /api/wallet/sign to get signature
   └─ AVNU paymaster pays gas
   └─ Transaction lands on Starknet
        │
        ▼
3. App shows "Earning 3.33% APY on BTC"
   └─ Links to Voyager explorer for the tx

The user saw: one button tap. Behind the scenes: wallet creation, account deployment, pool discovery, staking transaction construction, server-side signing, gas sponsorship, and on-chain execution — all handled by Starkzap + Privy + AVNU.

Troubleshooting

"Network request failed" on mobile

The app uses EXPO_PUBLIC_API_URL from your .env. Common issues:

localhost on a real device — use your machine's LAN IP instead (e.g. http://192.168.1.5:3000)
Backend not running — run cd backend && npm run dev
Wrong port — check PORT in backend/.env, default is 3000

Quick check: open EXPO_PUBLIC_API_URL/health in a browser — you should see {"ok":true}.

"AVNU_PAYMASTER_API_KEY is required"

All DeFi operations (stake, deploy) require the paymaster. Get a free key from portal.avnu.fi.

"No LBTC staking pool found"

Native LBTC staking may not be available on Sepolia. Try mainnet (STARKNET_NETWORK=mainnet) or set BTC_STAKING_CONTRACT_ADDRESS for a custom contract.

Resources

Starkzap documentation — docs.starknet.io/build/starkzap
Starkzap Privy integration — docs.starknet.io/build/starkzap/integrations/privy
Starkzap Paymasters — docs.starknet.io/build/starkzap/paymasters
AVNU Paymaster integration — docs.starknet.io/build/starkzap/integrations/avnu-paymaster
Starkzap Connecting Wallets — docs.starknet.io/build/starkzap/connecting-wallets
AVNU Portal — portal.avnu.fi
Privy Dashboard — dashboard.privy.io
Starknet Staking Dashboard — voyager.online/staking-dashboard

Built with Starkzap — the fastest way to add Starknet to any app.

Name		Name	Last commit message	Last commit date
Latest commit History 11 Commits
backend		backend
mobile		mobile
types		types
.gitignore		.gitignore
.gitkeep		.gitkeep
.watchmanconfig		.watchmanconfig
App.tsx		App.tsx
README.md		README.md
app.json		app.json
metro.config.js		metro.config.js
package-lock.json		package-lock.json
package.json		package.json
tsconfig.json		tsconfig.json

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SmoothYield — Add BTC Staking to Any TradFi App with Starkzap

Table of Contents

Why Add Crypto Rails to a TradFi App?

Architecture Overview

Starkzap Modules Used

Step-by-Step: How Starkzap Is Integrated

Step 1: Install Starkzap

Step 2: Get Your API Keys

Step 3: Initialize the Starkzap SDK

Step 4: Create Invisible Wallets with Privy

Step 5: Onboard a Wallet into Starkzap

Step 6: Read Token Balances

Step 7: Stake LBTC for Yield

Step 8: Unstake and Withdraw

The Paymaster: Gasless Transactions

Project Structure

Quick Start

1. Backend

2. Mobile

3. Dev Mode

Environment Variables

Backend (`backend/.env`)

Mobile (`mobile/.env`)

API Reference

End-to-End Yield Flow

Troubleshooting

"Network request failed" on mobile

"AVNU_PAYMASTER_API_KEY is required"

"No LBTC staking pool found"

Resources

About

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Latest commit

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Repository files navigation

SmoothYield — Add BTC Staking to Any TradFi App with Starkzap

Table of Contents

Why Add Crypto Rails to a TradFi App?

Architecture Overview

Starkzap Modules Used

Step-by-Step: How Starkzap Is Integrated

Step 1: Install Starkzap

Step 2: Get Your API Keys

Step 3: Initialize the Starkzap SDK

Step 4: Create Invisible Wallets with Privy

Step 5: Onboard a Wallet into Starkzap

Step 6: Read Token Balances

Step 7: Stake LBTC for Yield

Step 8: Unstake and Withdraw

The Paymaster: Gasless Transactions

Project Structure

Quick Start

1. Backend

2. Mobile

3. Dev Mode

Environment Variables

Backend (backend/.env)

Mobile (mobile/.env)

API Reference

End-to-End Yield Flow

Troubleshooting

"Network request failed" on mobile

"AVNU_PAYMASTER_API_KEY is required"

"No LBTC staking pool found"

Resources

About

Resources

Stars

Watchers

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Backend (`backend/.env`)

Mobile (`mobile/.env`)