Cross-Chain Bridge

Bridge assets to/from StarkNet via NEAR Intents / 1-Click protocol. Supports Solana, Ethereum, Base, Arbitrum, NEAR, and other chains.

Overview

Sable’s bridge integration allows users to:

Bridge IN: Send tokens from any chain → receive STRK on StarkNet
Bridge OUT: Send STRK from StarkNet → receive tokens on any chain

All bridges are powered by NEAR Intents (1-Click protocol), a decentralized solver network that finds optimal routes across chains.

Supported Chains

Chain	Bridge IN	Bridge OUT	Popular Tokens
Ethereum	✓	✓	ETH, USDC, WBTC
Solana	✓	✓	SOL, USDC
Base	✓	✓	ETH, USDC
Arbitrum	✓	✓	ETH, USDC, ARB
Polygon	✓	✓	MATIC, USDC
Avalanche	✓	✓	AVAX, USDC
NEAR	✓	✓	NEAR, USDC
Optimism	✓	✓	ETH, USDC, OP

Bridge availability depends on NEAR Intents solver network. Some routes may be unavailable during low liquidity periods.

Bridge Architecture

BRIDGE IN (External Chain → StarkNet):
  ┌──────────┐    deposit     ┌──────────────┐    intents    ┌──────────┐
  │ Solana / │ ───────────► │ NEAR 1-Click │ ──────────► │ StarkNet │
  │ Ethereum │    (SOL/ETH)   │ Protocol     │    (swap +    │ Wallet   │
  │ Base ... │                │ (Intents)    │    bridge)    │ (STRK)   │
  └──────────┘                └──────────────┘               └──────────┘

BRIDGE OUT (StarkNet → External Chain):
  ┌──────────┐   STRK transfer  ┌──────────────┐   intents   ┌──────────┐
  │ StarkNet │ ──────────────► │ NEAR 1-Click │ ─────────► │ Solana / │
  │ Wallet   │   to deposit     │ Protocol     │   (swap +   │ Ethereum │
  │          │   address        │ (Intents)    │   bridge)   │ etc.     │
  └──────────┘                  └──────────────┘              └──────────┘

Bridge Flow

Bridge IN (to StarkNet)

Select Source Chain & Token

Choose the chain and token you want to bridge from:

const bridgeIn = {
  sourceChain: "Ethereum",
  sourceToken: "USDC",
  amount: "100",
  destinationChain: "StarkNet",
  destinationToken: "STRK"
}

Get Quote

Fetch a quote from NEAR Intents API:

const quote = await fetch('https://api.1click.near.org/quote', {
  method: 'POST',
  body: JSON.stringify({
    from_chain: 'ethereum',
    from_token: 'USDC',
    to_chain: 'starknet',
    to_token: 'STRK',
    amount: '100000000',  // 100 USDC (6 decimals)
    dry_run: true
  })
});

// Returns estimated output amount and route

dry_run: true provides an estimate without creating a deposit address. Set to false for actual bridge.

Confirm & Get Deposit Address

User confirms the quote. Request actual bridge with dry_run: false:

const bridge = await fetch('https://api.1click.near.org/quote', {
  method: 'POST',
  body: JSON.stringify({
    ...quote,
    dry_run: false,
    recipient: '0x...starknet_wallet_address'
  })
});

// Returns deposit address on source chain
const depositAddress = bridge.deposit_address;

Deposit Tokens

User sends tokens to the deposit address on source chain:

From: User's Ethereum wallet
To: 0x...deposit_address (Ethereum)
Amount: 100 USDC

Only send the exact token and amount specified in the quote. Other tokens will be lost.

Wait for Settlement

NEAR Intents solver network:

Detects deposit on source chain (~30s)
Swaps tokens to intermediate assets if needed
Bridges to StarkNet
Swaps to STRK on StarkNet DEXes
Sends STRK to recipient wallet

Typical time: 30-60 seconds

Receive STRK

STRK arrives in your StarkNet wallet. Bridge complete!

Bridge OUT (from StarkNet)

Select Destination Chain & Token

Choose where you want to send your STRK:

const bridgeOut = {
  sourceChain: "StarkNet",
  sourceToken: "STRK",
  amount: "100",
  destinationChain: "Ethereum",
  destinationToken: "USDC"
}

Get Quote & Deposit Address

Similar to Bridge IN, but STRK is the source token:

const quote = await fetch('https://api.1click.near.org/quote', {
  method: 'POST',
  body: JSON.stringify({
    from_chain: 'starknet',
    from_token: 'STRK',
    to_chain: 'ethereum',
    to_token: 'USDC',
    amount: '100000000000000000000',  // 100 STRK (18 decimals)
    dry_run: false,
    recipient: '0x...ethereum_wallet_address'
  })
});

const depositAddress = quote.deposit_address;  // StarkNet address

Transfer STRK

Send STRK to the deposit address on StarkNet:

STRK.transfer(deposit_address, 100_000000000000000000)

Use Sable’s bridge interface to auto-fill the transfer transaction.

Wait for Settlement

NEAR Intents processes the bridge:

Detects STRK transfer on StarkNet
Swaps STRK to intermediate assets
Bridges to destination chain
Swaps to destination token
Sends to recipient

Typical time: 30-90 seconds (depends on destination chain finality)

Receive Tokens

Destination tokens arrive in your wallet on the destination chain.

Bridge Status Tracking

Sable provides real-time status tracking:

GET /api/bridge/status?transaction_id=...

Response:
{
  "status": "processing",
  "steps": [
    {
      "step": "deposit_detected",
      "status": "completed",
      "timestamp": 1234567890,
      "tx_hash": "0x..."
    },
    {
      "step": "swap_source_token",
      "status": "completed",
      "timestamp": 1234567920
    },
    {
      "step": "bridge_to_destination",
      "status": "processing",
      "timestamp": null
    },
    {
      "step": "swap_destination_token",
      "status": "pending",
      "timestamp": null
    },
    {
      "step": "send_to_recipient",
      "status": "pending",
      "timestamp": null
    }
  ]
}

Status Values
Steps

Status	Description
`pending`	Step not yet started
`processing`	Step in progress
`completed`	Step finished successfully
`failed`	Step failed (bridge will auto-refund)

Fees & Pricing

Fee Structure

Total Cost = Source Amount + Bridge Fee + Gas Fees + Swap Fees

Bridge Fee: ~0.1-0.5% (NEAR Intents protocol fee)
Gas Fees: Varies by source/dest chain
  • Ethereum: $5-20
  • Solana: $0.01-0.10
  • StarkNet: $0.50-2
Swap Fees: ~0.1-0.3% per swap (DEX fees)

Example (Bridge IN from Ethereum):
  Input: 100 USDC
  Bridge fee: 0.20 USDC (0.2%)
  Gas (Ethereum): $10 (in ETH)
  Swap fee (StarkNet): 0.15 USDC (0.15%)
  
  Net received: ~99.65 USDC equivalent in STRK
  Total cost: $10 ETH + 0.35 USDC

Quote API returns exact output amount after all fees. No hidden costs.

Bridge Speed

Route	Typical Time	Notes
Ethereum → StarkNet	60-90s	Ethereum finality + StarkNet settlement
Solana → StarkNet	30-45s	Fast Solana finality
StarkNet → Ethereum	60-120s	StarkNet finality + Ethereum gas
StarkNet → Solana	45-60s	Fast Solana settlement
Base/Arbitrum → StarkNet	45-60s	L2 finality faster than Ethereum

During high network congestion, bridges may take 2-5x longer. Monitor status tracker for updates.

Security & Trust Model

NEAR Intents (1-Click)

Architecture: Decentralized solver network How it works:

User creates a bridge intent (“I want to send 100 USDC from Ethereum to STRK on StarkNet”)
Solvers compete to fulfill the intent at best price
Winning solver executes the swap + bridge + delivery
User receives funds on destination chain

Trust Assumptions:

Solvers are incentivized by fees to execute correctly
Failed bridges auto-refund to source chain
NEAR protocol validates solver actions

NEAR Intents is non-custodial. Funds route through smart contracts, not centralized custodians.

Refund Policy

Bridges can fail due to:

Destination chain congestion
Insufficient destination liquidity
Oracle price deviation

On failure:

NEAR Intents detects failed step
Auto-initiates refund to source chain
User receives original tokens back (minus gas fees)

Refund time: 1-24 hours (depends on source chain)

Gas fees are not refundable even if bridge fails.

Best Practices

Check Quote Carefully: Verify output amount before confirming
Use Test Amounts First: Bridge $10-20 before large transfers
Monitor Status: Don’t panic if bridge takes 2-3 minutes
Save Transaction ID: Bookmark status page for tracking
Bridge During Low Traffic: Avoid peak hours (US evenings) for faster settlement
Consider Gas Costs: Small bridges (under $100) pay high % fee due to gas

API Integration

Quote Endpoint

POST https://api.1click.near.org/quote

Request:
{
  "from_chain": "ethereum",
  "from_token": "USDC",
  "to_chain": "starknet",
  "to_token": "STRK",
  "amount": "100000000",
  "dry_run": false,
  "recipient": "0x..."
}

Response:
{
  "transaction_id": "abc123",
  "deposit_address": "0x...",
  "estimated_output": "95.2 STRK",
  "route": [
    {"step": "swap", "from": "USDC", "to": "ETH", "dex": "Uniswap"},
    {"step": "bridge", "from": "Ethereum", "to": "StarkNet"},
    {"step": "swap", "from": "ETH", "to": "STRK", "dex": "Jediswap"}
  ],
  "fees": {
    "bridge_fee": "0.20 USDC",
    "gas_estimate": "$8.50",
    "swap_fees": "0.15 USDC"
  }
}

Status Endpoint

GET https://api.1click.near.org/status?transaction_id=abc123

Response:
{
  "transaction_id": "abc123",
  "status": "completed",
  "output_amount": "95.18 STRK",
  "output_tx_hash": "0x...",
  "completion_time": 1234567890
}

Supported Tokens

Bridge IN (Source Chains)

Chain	Supported Tokens
Ethereum	ETH, USDC, USDT, WBTC, DAI
Solana	SOL, USDC, USDT
Base	ETH, USDC
Arbitrum	ETH, USDC, ARB
Polygon	MATIC, USDC
Avalanche	AVAX, USDC

Bridge OUT (Destination Chains)

All above tokens supported. Bridge OUT always sources from STRK on StarkNet.

Risk Factors

Bridge protocol risk: NEAR Intents solver network failure
Price volatility during bridge: Token price can change in 30-90s settlement
Smart contract risk: Bridge contracts on source/dest chains
Slippage: Swaps may execute at worse-than-quoted prices during high volatility
Refund delays: Failed bridges can take 24h to refund

Next Steps

Bridge to StarkNet

Step-by-step guide for Bridge IN

Bridge from StarkNet

Step-by-step guide for Bridge OUT

NEAR Intents Docs

Learn about the bridge protocol

Track Bridge Status

Monitor your cross-chain transfers

Get Started

Features

Protocol Integrations

Bridge

Cross-Chain Bridge

Overview

Supported Chains

Bridge Architecture

Bridge Flow

Bridge IN (to StarkNet)

Bridge OUT (from StarkNet)

Bridge Status Tracking

Fees & Pricing

Fee Structure

Bridge Speed

Security & Trust Model

NEAR Intents (1-Click)

Refund Policy

Best Practices

API Integration

Quote Endpoint

Status Endpoint

Supported Tokens

Bridge IN (Source Chains)

Bridge OUT (Destination Chains)

Risk Factors

Next Steps

Bridge to StarkNet

Bridge from StarkNet

NEAR Intents Docs

Track Bridge Status

Get Started

Features

Protocol Integrations

Documentation Index

​Cross-Chain Bridge

​Overview

​Supported Chains

​Bridge Architecture

​Bridge Flow

​Bridge IN (to StarkNet)

​Bridge OUT (from StarkNet)

​Bridge Status Tracking

​Fees & Pricing

​Fee Structure

​Bridge Speed

​Security & Trust Model

​NEAR Intents (1-Click)

​Refund Policy

​Best Practices

​API Integration

​Quote Endpoint

​Status Endpoint

​Supported Tokens

​Bridge IN (Source Chains)

​Bridge OUT (Destination Chains)

​Risk Factors

​Next Steps

Bridge to StarkNet

Bridge from StarkNet

NEAR Intents Docs

Track Bridge Status

Cross-Chain Bridge

Overview

Supported Chains

Bridge Architecture

Bridge Flow

Bridge IN (to StarkNet)

Bridge OUT (from StarkNet)

Bridge Status Tracking

Fees & Pricing

Fee Structure

Bridge Speed

Security & Trust Model

NEAR Intents (1-Click)

Refund Policy

Best Practices

API Integration

Quote Endpoint

Status Endpoint

Supported Tokens

Bridge IN (Source Chains)

Bridge OUT (Destination Chains)

Risk Factors

Next Steps