Rails

Rails are the foundational building blocks of the Swipelux transfer system. They represent different payment methods and networks that assets can move through, abstracting away the complexity of routing and conversion while providing a unified interface for all types of value transfer.

Philosophy: Rail-Agnostic Transfers

Swipelux treats all transfer rails equally, whether they're crypto networks or fiat payment methods. This rail-agnostic approach means you can seamlessly transfer value in any direction:

• Crypto → Crypto: From one blockchain to another
• Crypto → Fiat: From cryptocurrency to traditional payment methods
• Fiat → Crypto: From traditional payment methods to cryptocurrency
• Fiat → Fiat: Between different fiat payment methods

The beauty of this system is that routing complexity is handled under the hood. When you specify a transfer from "card" to "polygon", our system automatically:

• Finds the best onramp provider for card processing
• Identifies optimal swap routes for the best exchange rates
• Executes the transfer at the highest speed and lowest cost
• Handles all intermediate steps transparently

Types of Rails

Crypto Rails

Crypto rails represent different blockchain networks and protocols:

Fiat Rails

Fiat rails represent traditional payment methods and banking systems:

Transfer Examples

Cross-Rail Transfer: Card to Polygon

{
  "from": {
    "identifier": "cus_123",
    "amount": "100.00",
    "rail": "card",
    "currency": "USD"
  },
  "to": {
    "identifier": "cus_123",
    "rail": "polygon",
    "currency": "USDC"
  }
}

What happens behind the scenes:

1. Card payment is processed through our onramp partners
2. USD is converted to USDC at optimal rates
3. USDC is bridged to Polygon network
4. Final USDC balance appears in customer's Polygon wallet

Crypto-to-Crypto: Ethereum to Base

{
  "from": {
    "identifier": "cus_123",
    "amount": "50.00",
    "rail": "ethereum",
    "currency": "USDC"
  },
  "to": {
    "identifier": "0x742d35Cc6635Bb427C07Bcc1A484C96396bbBa2C",
    "rail": "base",
    "currency": "USDC"
  }
}

What happens behind the scenes:

1. USDC is debited from customer's Ethereum wallet
2. Cross-chain bridge routes the assets to Base network
3. USDC arrives at the specified Base address
4. All bridging fees and gas costs are optimized automatically

Multi-Hop Routing: Apple Pay to Binance

{
  "from": {
    "identifier": "cus_456",
    "amount": "75.50",
    "rail": "apple_pay", 
    "currency": "EUR"
  },
  "to": {
    "identifier": "cus_789",
    "rail": "binance",
    "currency": "USDC"
  }
}

What happens behind the scenes:

1. Apple Pay processes EUR payment
2. EUR is converted to USD via forex markets
3. USD is converted to USDC through our liquidity partners
4. USDC is bridged from Ethereum to Binance Smart Chain
5. Final USDC balance appears in recipient's Binance wallet

Transfer Types by Routing Complexity

Bridge Transfers (Cross-Chain)

Bridge transfers move the same currency across different blockchain networks. These are optimized for speed and cost across networks.

USDC Bridge: Ethereum to Polygon

{
  "from": {
    "identifier": "cus_123",
    "amount": "100.00",
    "rail": "ethereum",
    "currency": "USDC"
  },
  "to": {
    "identifier": "cus_123",
    "rail": "polygon",
    "currency": "USDC"
  }
}

Bridge routing:

• Same currency (USDC) on both sides
• Different networks (Ethereum → Polygon)
• Optimized for lowest bridge fees and fastest finality

USDC Bridge: Base to Arbitrum

{
  "from": {
    "identifier": "cus_456",
    "amount": "25.00",
    "rail": "base",
    "currency": "USDC"
  },
  "to": {
    "identifier": "0x1234567890abcdef1234567890abcdef12345678",
    "rail": "arbitrum",
    "currency": "USDC"
  }
}

Bridge routing:

• Layer 2 to Layer 2 bridging
• Direct cross-chain asset movement
• No currency conversion needed

Swap Transfers (Currency Exchange)

Swap transfers change currencies while potentially staying on the same rail or network.

Fiat Swap: USD to EUR via Wire Transfer

{
  "from": {
    "identifier": "cus_123",
    "amount": "1000.00",
    "rail": "wire_transfer",
    "currency": "USD"
  },
  "to": {
    "identifier": "cus_456",
    "rail": "wire_transfer", 
    "currency": "EUR"
  }
}

Swap routing:

• Same rail (wire_transfer) on both sides
• Different currencies (USD → EUR)
• Forex conversion with optimal rates

Cross-Asset Swap: USDC to USDT on Ethereum

{
  "from": {
    "identifier": "cus_123",
    "amount": "500.00",
    "rail": "ethereum",
    "currency": "USDC"
  },
  "to": {
    "identifier": "cus_123",
    "rail": "ethereum",
    "currency": "USDT"
  }
}

Swap routing:

• Same network (Ethereum) on both sides
• Different stablecoins (USDC → USDT)
• DEX routing for best exchange rates

Mixed Transfers (Bridge + Swap)

Mixed transfers combine currency conversion and network changes in a single operation.

Complex Route: EUR Card to USDT on Polygon

{
  "from": {
    "identifier": "cus_123",
    "amount": "200.00",
    "rail": "card",
    "currency": "EUR"
  },
  "to": {
    "identifier": "cus_123",
    "rail": "polygon",
    "currency": "USDT"
  }
}

Mixed routing:

1. EUR card payment processed
2. EUR → USD forex conversion
3. USD → USDC onramp conversion
4. USDC → USDT DEX swap on Polygon
5. Final USDT balance on Polygon

Multi-Hop: GBP Open Banking to USDC on Avalanche

{
  "from": {
    "identifier": "cus_456",
    "amount": "150.00",
    "rail": "open_banking",
    "currency": "GBP"
  },
  "to": {
    "identifier": "0x987654321098765432109876543210987654321",
    "rail": "avalanche",
    "currency": "USDC"
  }
}

Mixed routing:

1. GBP Open Banking payment
2. GBP → USD forex conversion
3. USD onramp to USDC on Ethereum
4. USDC bridge from Ethereum to Avalanche
5. Final USDC transfer to external address

Cross-Network Stablecoin Transfer

{
  "from": {
    "identifier": "cus_789",
    "amount": "75.00", 
    "rail": "base",
    "currency": "USDC"
  },
  "to": {
    "identifier": "cus_101112",
    "rail": "binance",
    "currency": "BUSD"
  }
}

Mixed routing:

1. USDC debited from Base network
2. Cross-chain bridge to Binance Smart Chain
3. USDC → BUSD swap on BSC
4. BUSD credited to recipient's wallet

Intelligent Routing

When you create a transfer, our system:

1. Evaluates all possible routes between the source and destination rails
2. Calculates total cost including fees, spreads, and gas
3. Estimates completion time based on current network conditions
4. Selects the optimal path balancing speed, cost, and reliability
5. Executes atomically with automatic rollback on failure

Rail Configuration

Different rails have different requirements and capabilities:

Network Rails (Crypto ↔ Crypto)

• Required fields: currency (e.g., "USDC") must be specified
• Destination: Can be customer wallet or external address
• KYC requirements: None for pure crypto transfers
• Processing time: Seconds to minutes depending on network

Cross-Rail Transfers

• Automatic conversion: Fiat ↔ crypto conversion handled seamlessly
• Multi-hop routing: Complex paths optimized automatically
• Atomic execution: All steps succeed or the entire transfer fails
• Transparent pricing: All fees disclosed upfront

Best Practices

Choosing Rails

For Speed: Use Layer 2 networks (see crypto rails table above) For Cost: Consider lower-cost networks for smaller amounts (see crypto rails table above)
For Compatibility: Ethereum has the widest ecosystem support For Fiat On/Off-ramps: Card and mobile payments offer the best user experience

Error Handling

Rails can experience temporary issues. Our system provides:

• Automatic retries for transient failures
• Alternative routing when primary paths fail
• Real-time status updates via webhooks
• Detailed error codes for troubleshooting

Monitoring

Track transfer performance across different rails:

• Success rates by rail and route
• Average completion times for planning user experiences
• Cost analysis to optimize your application's economics
• User preferences to suggest optimal rails for repeat customers

Future Rails

We're continuously expanding our rail support based on market demand and user feedback. Upcoming rails include:

Crypto: Solana, Cardano, Near Protocol, Cosmos Fiat: PayPal, Stripe Connect, Brazilian PIX, Indian UPI