MetaLayer API

Introduction

MetaLayer API is a comprehensive solution for projects that need token transfer functionality between blockchains. Instead of building and maintaining your own bridge infrastructure (validators, relayers, smart contracts), you can use our unified API.

This saves months of development and significant operational costs, allowing you to focus on growing your core product.

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The Problem

Who This Is For

Teams that need cross-chain transfers in their product:

• Crypto wallets

• DEX and aggregators

• DeFi protocols

• Payment gateways

• Financial services

Challenges of Building Your Own

• Smart contract development and auditing for each network

• Maintaining and securing validators and relayers

• 24/7 monitoring and support

• Continuously expanding the list of supported networks

• Finding optimal routes for users

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The Solution: MetaLayer API

We provide all the complex cross-chain bridge infrastructure through a single REST API.

What You Get

Capability	Description
Single API	One interface for dozens of blockchains
Route aggregation	Automatic search for best transfer paths
Ready transactions	API builds calldata — just send to blockchain
Status tracking	Monitor operations from start to finish
Fee configuration	Flexible business logic for your product
Continuous expansion	New networks and tokens added by our team

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Core Features

Route Aggregation

Search for optimal transfer path among multiple available routes and liquidity pools. The algorithm considers:

• Network and protocol fees

• Available liquidity

• Execution time

• Price impact

Priority Routes

Ability to configure exclusive, most favorable routes for your project. Partnership terms available upon request.

Simple Integration

• All operations via REST API

• No need for your own nodes

• Ready calldata for transactions

• Detailed documentation and examples

Extensive Network Support

Category	Networks
EVM L1	Ethereum, BSC, Polygon, Avalanche
EVM L2	Arbitrum, Optimism, Base, zkSync, Linea
Others	Continuously expanding

How It Works

┌─────────────────┐      ┌─────────────────┐      ┌─────────────────┐
│      Your       │      │   MetaLayer     │      │   Blockchain    │
│   Application   │◀────▶│      API        │      │    (Source)     │
└────────┬────────┘      └─────────────────┘      └────────▲────────┘
         │                                                  │
         │                 User sends TX                    │
         └──────────────────────────────────────────────────┘
                                                            │
                                                  Relayers / Validators
                                                            │
                                                            ▼
                                                 ┌─────────────────┐
                                                 │   Blockchain    │
                                                 │  (Destination)  │
                                                 └─────────────────┘

Step 1: Request Routes

Your application requests possible routes for transfer from network A to network B.

POST /routing/scan
{
  "params": {
    "chainIdIn": 1,        // Ethereum
    "chainIdOut": 42161,   // Arbitrum
    "tokenIn": "0x...",
    "tokenOut": "0x...",
    "amountIn": "1000000000000000000"
  },
  "slippage": 1
}

Step 2: Select Route

API returns options with estimated time, fees, and output amount. Your application selects the best one.

{
  "amountOut": "998500000",
  "priceImpact": 0.15,
  "totalFee": { "percent": "0.15" },
  "expectedFinalitySeconds": "180"
}

Step 3: Get Estimate

Request signature and final parameters for the selected route.

POST /estimate
→ { "executionPrice": "...", "deadline": "...", "signature": "0x..." }

Step 4: Build Transaction

Get ready data for blockchain submission.

POST /tx/create (with buildCalldata: true)
→ { "to": "0x...", "data": "0x...", "value": "0" }

Step 5: Send and Track

User signs and sends transaction. Monitor status via REST API or WebSocket.

GET /transaction/{requestId}
→ { "status": "in progress" | "completed" }

Step 6: Completion

Transfer completes in the destination network. All confirmation and relay logic is handled by MetaLayer infrastructure.

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Getting Started

For Developers

Detailed technical documentation with code examples:

• API Reference: Complete description of all endpoints

• Quick Start: Step-by-step integration guide

Go to Developer Documentation →

Resources

Resource	Link
Swagger UI	https://api.crosscurve.fi/api-docs/
API Base URL	https://api.crosscurve.fi
Documentation	https://docs.crosscurve.fi

For Business

To discuss integration terms, partnership rates, and get test access, contact our team:

• Custom terms discussion

• Priority routes for your project