Introduction
ArbiLink is a universal cross-chain messaging protocol that makes Arbitrum the hub for multi-chain communication. Instead of deploying your dApp on every chain and managing separate bridges, you deploy once on Arbitrum and reach users everywhere.
The Problem
Cross-chain development today is fragmented and expensive:
- You need separate deployments on Ethereum, Base, Polygon, Optimism…
- Each chain requires its own bridge integration with different APIs
- Security audits multiply — one per chain
- Gas costs are high: $4.50+ per message on existing bridges
- Development takes weeks per chain
The ArbiLink Solution
One Arbitrum contract → One SDK call → Any chainArbiLink provides:
- Single integration point on Arbitrum Sepolia
- $0.23/message via Arbitrum Stylus efficiency
- ~12 second delivery with real-time tracking
- Optimistic security with fraud-proof challenge window
- Fully typed TypeScript SDK — 3 lines to send a message
Architecture Overview
┌──────────────────────┐ ┌─────────────────────────┐
│ Your dApp │ │ Destination Chain │
│ (Arbitrum) │ │ (Ethereum / Base / …) │
│ │ │ │
│ ArbiLink SDK │ │ ArbiLinkReceiver.sol │
│ sendMessage() ─────┼──┬───►│ receiveMessage() │
│ │ │ │ → executes your target │
│ MessageHub.sol │ │ └─────────────────────────┘
│ (Rust / Stylus) │ │
└──────────────────────┘ │ ┌─────────────────────────┐
└───│ Relayer Network │
│ (off-chain, staked) │
└─────────────────────────┘Components
| Component | Language | Role |
|---|---|---|
MessageHub | Rust (Stylus) | On-chain message registry on Arbitrum |
ArbiLinkReceiver | Solidity | Receiver contract on every destination chain |
| Relayer Network | Off-chain | Detects events, delivers messages, stakes ETH |
@arbilink/sdk | TypeScript | Developer SDK for sending & tracking messages |
Security Model
ArbiLink uses an optimistic approach:
- Relayers stake ETH to participate (
RELAYER_STAKE = 0.1 ETH) - Messages are executed optimistically on the destination chain
- A 5-minute challenge window allows anyone to dispute invalid deliveries
- Fraudulent relayers are slashed — their stake is redistributed
- Honest relayers earn fees for every delivery
No Trusted Intermediaries
ArbiLink does not rely on a multisig, oracle committee, or any centralised entity. Security comes from economic incentives and fraud proofs.