Overview

ZecretPipe is a privacy-first cross-chain messaging service between Starknet and Zcash.

Unlike traditional bridges that only transfer tokens, ZecretPipe can transmit arbitrary data (as long as it can be cryptographically proven). This enables advanced use cases beyond simple asset transfers, including:

• dApp coordination: Cross-chain smart contract interactions and composability
• Privacy-preserving credentials: Anonymous identity verification and authentication across chains
• Custom applications: Developers can build their own cross-chain applications on top of ZecretPipe by designing custom payload formats

Because ZecretPipe transmits verifiable information rather than just assets, it serves as a general-purpose messaging infrastructure that unlocks true cross-chain interoperability.

Starknet ←→ [Messaging Layer] ←→ Zcash
    ↓                          ↓                                ↓
  Events                 Relay                       Memo Field
  State                   Verify                    Transactions
  Contracts            Route                          Notes

The messaging layer provides the following capabilities:

• Event listening - Monitors state changes on both chains in real-time
• Message routing - Securely relays messages between chains with encryption
• Action triggering - Triggers corresponding actions on the destination chain automatically
• Verification - Ensures message integrity and authenticity of the source through cryptographic proofs

Acts as an orchestrator and relay layer that listens to transactions or state changes on one chain and securely mirrors or triggers corresponding actions on the other (cross chain interoperability).

Why ZecretPipe Matters?

1. Infrastructure Play: Building a protocol layer, not just a single application—enabling an entire ecosystem of cross-chain dApps
2. First Mover Advantage: First-ever Starknet ↔ Zcash cross-chain messaging protocol
3. Real Value: Solves actual needs for both ecosystems:
   • Starknet: Gains privacy features leveraging Zcash's zero-knowledge technology
   • Zcash: Gains DeFi composability and smart contract capabilities through Starknet integration
4. Scalability & Extensibility:
   • Today: Starknet ↔ Zcash messaging
   • Tomorrow: Extensible architecture to support any chain
   • Future: Become a universal privacy-preserving cross-chain messaging standard

Application Examples

What we can build based on ZecretPipe as Infrastructure.

Developers can design their own encoding formats in the payload—such as adding nonce, expiration, signature, etc.—to build custom applications on top of ZecretPipe for message passing and verification.

1. Privacy-Preserving DeFi Bridge (wZEC)

   • Wrap Zcash assets to use in Starknet DeFi protocols
   • Maintain transaction privacy while enabling DeFi composability
   • Bridge liquidity between privacy-focused and DeFi ecosystems

2. Cross-Chain Notifications

   • DeFi protocols notify users about liquidations, yield opportunities, or governance proposals
   • Privacy-preserving alerts that don't reveal user identities or holdings
   • Smart contract events trigger encrypted notifications across chains

3. Anonymous Voting System

   • DAO voting while preserving voter privacy
   • Voting records stored publicly on Starknet for transparency
   • Voter identities verified through Zcash for anonymity
   • Prevents vote buying and coercion while maintaining verifiability

4. Cross-Chain Identity Verification

   • Prove cross-chain identity without revealing the specific address linkage
   • Starknet users prove they control a Zcash address without exposing which one
   • Enable privacy-preserving reputation systems across chains

Security and Trust Consideration

Relayer Network Design

Phase 0 - Centralized MVP

Just Zecret Official Relayer

Phase 1 - Half Decentralized

• Relay Node 1 (Starkware)
• Relay Node 2 (Zcash ECC)
• Relay Node 3 (Trustworthy Community)
• Relay Node 4 (ZecretPipe Official)
• Relay Node 5 (Trustworthy Partner)

Phase 2 - Totally Decentralized

• Relayer Network
• Reputation Mechanism
• Challenge Mechanism
• Staking Mechanism (stake ETH/STRK tokens)
• Economic Security: Slash malicious relayers & Reward honest behavior

Privacy Solution

Method A: Subscription Notifications (Lower Privacy)

• Pros: Real-time notifications, excellent user experience
• Cons: Relay knows you're expecting messages (metadata leakage)

Method B: Stealth Addresses (Medium Privacy)

• Pros: Recipients can efficiently filter messages meant for them
• Cons: High technical complexity to implement

Method C: Active Scanning (Highest Privacy)

• Pros: Complete privacy—no one knows you received a message
• Cons: Requires scanning all messages, lower efficiency