Nodus Protocol — Core Engine

The payment processing backbone of the Nodus Protocol ecosystem.
Fast, composable, and built for the decentralized web.

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What is the Core Engine?

The Nodus Protocol Core Engine is the settlement and routing layer that powers seamless, permissionless payments across the Nodus ecosystem. It abstracts away the complexity of multi-chain transactions so that users and developers can move value as easily as sending a message.

Whether you're building a checkout flow, a subscription service, or a cross-chain payment app, the Core Engine handles the heavy lifting — routing, validation, settlement, and confirmation.

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Features

• One-click payments — Customers initiate transfers without managing gas, bridges, or slippage manually.
• Multi-chain routing — Automatically selects the optimal path across supported Substrate networks (Aleph Zero, Astar, Shiden) to minimize cost and latency.
• Instant settlement — Transactions are confirmed and settled in seconds, not minutes.
• Non-custodial — The engine never holds user funds; all transfers go directly between parties.
• Composable — Drop the engine into any stack via a clean API and SDK.
• Auditable — Every payment produces an on-chain receipt, queryable at any time.

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How It Works

Customer initiates payment
        │
        ▼
 Core Engine receives request
        │
        ├─ Validates sender & recipient
        ├─ Selects optimal chain route
        ├─ Estimates & abstracts fees
        │
        ▼
 Transaction submitted on-chain
        │
        ▼
 Settlement confirmed + receipt emitted
        │
        ▼
 Merchant/recipient notified

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Getting Started

Prerequisites

• Rust 1.80+ (2024 edition)
• Cargo
• An RPC endpoint for your target network

Installation

git clone https://github.com/Nodus-protocol/Nodus-Protocol-Core-Engine.git
cd Nodus-Protocol-Core-Engine
cargo build

Configuration

Copy the example environment file and fill in your values:

cp .env.example .env

Variable	Description
RPC_URL	Substrate RPC endpoint for the target chain (e.g. Aleph Zero, Astar)
PRIVATE_KEY	SR25519 signing key (SS58 format) for the engine wallet
SETTLEMENT_CONTRACT	SS58 address of the deployed LiquidityPool contract
NETWORK	Target network (mainnet, testnet)

Running locally

cargo run

Running tests

cargo test

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API Overview

Initiate a payment

POST /api/v1/pay
Content-Type: application/json

{
  "from": "5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY",
  "to": "5FHneW46xGXgs5mUiveU4sbTyGBzmstUspZC92UhjJM694ty",
  "amount": "50.00",
  "currency": "USDC",
  "network": "aleph-zero"
}

Response

{
  "status": "confirmed",
  "txHash": "0xabc123...",
  "settledAt": "2025-01-01T12:00:00Z",
  "fee": "0.001 USDC",
  "receipt": "ipfs://Qm..."
}

Query a payment

GET /api/v1/pay/:txHash

Supported tokens

Symbol	Network
AZERO	Aleph Zero
USDC	Aleph Zero (PSP22)
USDT	Aleph Zero (PSP22)
DOT	Astar, Shiden
ASTR	Astar

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SDK

A JavaScript/TypeScript SDK is available for easy integration:

import { NodusEngine } from "@nodus/core-engine"

const engine = new NodusEngine({ network: "aleph-zero" })

const receipt = await engine.pay({
  from: "5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY",
  to: "5FHneW46xGXgs5mUiveU4sbTyGBzmstUspZC92UhjJM694ty",
  amount: "100",
  currency: "USDC",
})

console.log(receipt.txHash)

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Project Structure

Nodus-Protocol-Core-Engine/
├── src/
│   ├── engine/         # Core payment routing & settlement logic
│   ├── adapters/       # Chain-specific adapters (EVM, etc.)
│   ├── api/            # REST API handlers
│   └── utils/          # Helpers, fee estimation, validation
├── contracts/          # On-chain settlement contracts
├── tests/              # Unit and integration tests
└── docs/               # Extended documentation

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Contributing

Contributions are welcome. Please read CONTRIBUTING.md before opening a pull request.

1. Fork the repo
2. Create your branch: git checkout -b feat/your-feature
3. Commit your changes with a clear message
4. Push to your fork and open a PR against main

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Security

If you discover a vulnerability, please do not open a public issue. Contact the team privately at security@nodusprotocol.io.

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License

MIT © Nodus Protocol