DisseK — Selective Disclosure of Knowledge

Prove what you share. Hide what you don't.

DisseK is a decentralised marketplace where data owners sell cryptographically verified slices of their documents — without ever exposing the rest. Buyers (humans or AI agents) pay via stablecoin micropayments, receive the exact lines they purchased, and get a Merkle range proof that mathematically guarantees authenticity. No trust required.

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How It Works

1. Publisher uploads a document to Fileverse, builds a Merkle tree over every line, and anchors the root on-chain
2. Buyer browses the marketplace, picks a section (or custom line range), and clicks purchase
3. Host backend generates a selective disclosure: only the purchased lines + a multi-proof
4. Buyer verifies the proof against the on-chain Merkle root — if it matches, the data is authentic

The undisclosed lines never leave the host. The marketplace never sees full document content. Verification is free and permissionless.

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Tech Stack

proof-engine/     Rust → WASM    Merkle tree + range proofs (rs_merkle, sha2)
backend/          Express.js     Host server — Fileverse integration, proof generation
marketplace/      Express.js     Public directory — listings, purchase relay, Firestore/in-memory store
frontend/         React + Vite   SPA — wallet connect (MetaMask + SIWE), purchase, verify
contracts/        Solidity       MerkleAnchor.sol — on-chain root registry (Foundry)

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Fileverse Integration

DisseK uses Fileverse as its decentralised document storage layer, accessed via the Model Context Protocol (MCP).

• Documents live as Fileverse dDocs — decentralised, blockchain-synced, and content-addressed
• The host backend connects to Fileverse's MCP server using @modelcontextprotocol/sdk with StreamableHTTPClientTransport
• When a publisher lists a document, DisseK reads it from Fileverse, builds the Merkle tree, and stores only the root hash on-chain
• When a buyer purchases a section, a new partial dDoc is created on Fileverse containing only the disclosed lines (no proof data, just clean content)
• The buyer gets a Fileverse link to the disclosure document plus the proof package separately

The marketplace itself never touches document content — it only stores metadata, section definitions, and Merkle roots. All content flows through Fileverse, keeping the system truly decentralised.

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ENS Integration

ENS is the identity layer that powers access control for both individuals and organizations.

For Individuals

When a wallet connects, we do bidirectional ENS resolution — reverse lookup (0xABC → alice.eth) followed by forward verification (alice.eth → 0xABC). Only if both match is the identity considered verified. This prevents anyone from spoofing someone else's name.

For Organizations & AI Agents

This is where it gets interesting. An organization like Google owns google.eth. Each of their AI agents gets a subname — agent-42.google.eth. When the organization purchases a dataset section, they buy a namespace grant for google.eth. Now any agent under *.google.eth automatically gets access.

ENSIP-25 — Trustless Agent Verification

To prevent rogue subnames, we implement ENSIP-25. The parent domain owner must set an ENS text record (with an ERC-7930 encoded registry address) attesting that the agent is registered in an ERC-8004 on-chain identity registry. Our system reads that text record directly from the ENS resolver — one lookup, fully trustless, no middleman.

This makes ENS the identity primitive for agent-to-agent data commerce.

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Challenges & Learnings

Rust WASM compilation has target-specific quirks. The proof engine must be compiled with --target nodejs for the backend. The leaf array also needs padding to the next power-of-two — a requirement of rs_merkle that isn't obvious from the docs.

Fileverse document creation is async. When generating a disclosure, the new partial dDoc syncs to the blockchain asynchronously. We had to treat the Fileverse link as best-effort and return the proof package immediately.

ENSIP-25 involves two independent chain IDs. The ERC-8004 registry can be on Base Sepolia while the ENS text records live on Ethereum mainnet. Getting the ERC-7930 encoding right across chains required careful byte-level packing.

Browser polyfills for crypto libraries. The siwe package depends on Node.js Buffer which doesn't exist in browsers. Required a global polyfill in main.tsx before any other imports.

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Setup

Prerequisites

https://youtu.be/30YRtetrvGY

• Rust + wasm-pack — for compiling the proof engine
• Node.js ≥ 20 — for all three servers
• MetaMask — for wallet connection

Quick Start

# 1. Build the WASM proof engine
cd proof-engine && wasm-pack build --target nodejs --out-dir pkg && cd ..

# 2. Install dependencies
cd backend && npm install && cd ..
cd marketplace && npm install && cd ..
cd frontend && npm install && cd ..

# 3. Configure environment
cp backend/.env.example backend/.env
cp marketplace/.env.example marketplace/.env

# 4. Start all servers
bash restart.sh

# Or manually:
# cd backend && npm run dev &
# cd marketplace && npm run dev &
# cd frontend && npm run dev &

Verify

curl http://localhost:3001/health        # Host backend
curl http://localhost:3002/api/health    # Marketplace
# Frontend at http://localhost:5173

See individual directory READMEs for more details:

• backend/README.md
• marketplace/README.md
• frontend/README.md
• proof-engine/README.md
• contracts/README.md

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Future Goals

• Agent-native SDK — a standalone TypeScript/Python client that lets AI agents discover, purchase, and verify data without a browser
• Multi-chain support — deploy MerkleAnchor on multiple L2s, support cross-chain proof verification
• Reputation oracle — move the host reputation system on-chain, let verified purchases and successful verifications increase reputation automatically
• Encrypted disclosures — encrypt disclosed lines with the buyer's public key so only they can read the content, even if the response is intercepted
• ENSIP-25 delegation UI — a frontend for organizations to register agents and set text records without touching a CLI
• Fileverse IPFS pinning — pin disclosure documents to IPFS for long-term availability beyond Fileverse's sync window

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License

MIT