Architecture

Architecture

SIP Protocol operates as an application layer between user applications and the NEAR Intents settlement system.

System Overview

┌─────────────────────────────────────────────────────────────────┐
│                      APPLICATION LAYER                          │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐              │
│  │   DApps     │  │   Wallets   │  │    DAOs     │              │
│  └──────┬──────┘  └──────┬──────┘  └──────┬──────┘              │
│         │                │                │                      │
│         └────────────────┼────────────────┘                      │
│                          ▼                                       │
│  ┌───────────────────────────────────────────────────────────┐  │
│  │                    @sip-protocol/sdk                       │  │
│  │  ┌─────────┐ ┌─────────┐ ┌─────────┐ ┌─────────────────┐  │  │
│  │  │ Intent  │ │ Stealth │ │ Privacy │ │ Wallet Adapters │  │  │
│  │  │ Builder │ │ Address │ │ Manager │ │ (ETH/SOL/NEAR)  │  │  │
│  │  └─────────┘ └─────────┘ └─────────┘ └─────────────────┘  │  │
│  └───────────────────────────────────────────────────────────┘  │
│                          │                                       │
├──────────────────────────┼───────────────────────────────────────┤
│                   PRIVACY LAYER (SIP)                            │
│  ┌───────────────────────┴───────────────────────────────────┐  │
│  │  ┌──────────────┐  ┌──────────────┐  ┌──────────────────┐ │  │
│  │  │   Pedersen   │  │   Stealth    │  │   Viewing Keys   │ │  │
│  │  │ Commitments  │  │  Addresses   │  │  (Compliance)    │ │  │
│  │  └──────────────┘  └──────────────┘  └──────────────────┘ │  │
│  │  ┌──────────────┐  ┌──────────────┐  ┌──────────────────┐ │  │
│  │  │   Funding    │  │   Validity   │  │   Fulfillment    │ │  │
│  │  │    Proof     │  │    Proof     │  │     Proof        │ │  │
│  │  └──────────────┘  └──────────────┘  └──────────────────┘ │  │
│  └───────────────────────────────────────────────────────────┘  │
│                          │                                       │
├──────────────────────────┼───────────────────────────────────────┤
│                   SETTLEMENT LAYER                               │
│  ┌───────────────────────┴───────────────────────────────────┐  │
│  │              NEAR Intents + Chain Signatures               │  │
│  │  ┌──────────────┐  ┌──────────────┐  ┌──────────────────┐ │  │
│  │  │  1Click API  │  │   Solvers    │  │ Chain Signatures │ │  │
│  │  └──────────────┘  └──────────────┘  └──────────────────┘ │  │
│  └───────────────────────────────────────────────────────────┘  │
│                          │                                       │
├──────────────────────────┼───────────────────────────────────────┤
│                    BLOCKCHAIN LAYER                              │
│  ┌────────┐  ┌────────┐  ┌────────┐  ┌────────┐  ┌────────┐    │
│  │  NEAR  │  │  ETH   │  │ Solana │  │ Zcash  │  │Bitcoin │    │
│  └────────┘  └────────┘  └────────┘  └────────┘  └────────┘    │
└─────────────────────────────────────────────────────────────────┘

SDK Components

SIP Client

The main entry point that orchestrates all operations:

const sip = new SIP({
  network: 'testnet',
  proofProvider: new MockProofProvider(),
})

IntentBuilder

Fluent API for constructing shielded intents:

const intent = await sip
  .intent()
  .input('solana', 'SOL', amount)
  .output('ethereum', 'ETH')
  .privacy(PrivacyLevel.SHIELDED)
  .build()

Wallet Adapters

Chain-specific wallet integrations:

Adapter	Chain	Provider
EthereumWalletAdapter	Ethereum	MetaMask, WalletConnect
SolanaWalletAdapter	Solana	Phantom, Solflare
MockWalletAdapter	Testing	Mock provider

Proof Providers

ZK proof generation interfaces:

Provider	Status	Use Case
MockProofProvider	Available	Testing, development
NoirProofProvider	Planned	Production

Data Flow

Transparent Flow

User Intent → Standard intent → Solver → Settlement

No privacy features. All data visible on-chain.

Shielded Flow

User Intent
    ↓
Generate stealth address (recipient privacy)
    ↓
Create Pedersen commitments (amount privacy)
    ↓
Generate ZK proofs (funding + validity)
    ↓
Submit shielded intent
    ↓
Solver fulfills (only sees commitments)
    ↓
Fulfillment proof generated
    ↓
Settlement to stealth address

Compliant Flow

Same as shielded, plus:

• Encrypt transaction metadata with viewing key
• Auditor can decrypt specific transactions
• ViewingProof for audit reports

Cryptographic Components

Pedersen Commitments

C = value·G + blinding·H

• Perfectly hiding: Cannot extract value from C
• Computationally binding: Cannot change value after commit
• Homomorphic: C₁ + C₂ commits to sum of values

Stealth Addresses

Based on EIP-5564:

1. Recipient publishes meta-address (P, Q)
2. Sender generates ephemeral key r
3. Sender computes stealth address A = Q + H(r·P)·G
4. Recipient scans for R values, derives private key

Viewing Keys

Hierarchical key derivation:

Master Viewing Key
    ├── Full Viewing Key (all transactions)
    ├── Auditor Key (time-limited)
    └── Transaction Key (single transaction)

Encryption: XChaCha20-Poly1305 with HKDF key derivation.

Network Adapters

NEAR Intents Adapter

Connects to NEAR’s 1Click API for cross-chain settlement:

const adapter = new NEARIntentsAdapter({
  network: 'testnet',
  endpoint: 'https://1click.chaindefuser.com',
})

Zcash Shielded Service

Handles Zcash-specific shielded transactions:

const zcash = new ZcashShieldedService({
  rpcUrl: 'http://localhost:8232',
})

Key Files

File	Purpose
packages/sdk/src/sip.ts	Main SIP client
packages/sdk/src/intent.ts	IntentBuilder
packages/sdk/src/stealth.ts	Stealth addresses
packages/sdk/src/crypto.ts	Pedersen commitments
packages/sdk/src/privacy.ts	Viewing keys
packages/sdk/src/proofs/	Proof providers
packages/sdk/src/adapters/	Network/wallet adapters

Performance

Operation	Time (avg)
Generate meta-address	0.9ms
Derive stealth address	5.4ms
Create commitment	7.2ms
Verify commitment	6.6ms
Full shielded intent	~25ms

Measured on Apple M1, Node.js 20.

Tech Stack

• Language: TypeScript (strict)
• Monorepo: pnpm + Turborepo
• Crypto: @noble/curves, @noble/hashes, @noble/ciphers
• Testing: Vitest
• CI/CD: GitHub Actions