### Terms and Conditions
- [x] I agree to the [Grant Agreement](https://9ba4718…c-5c73-47c3-a024-4fc4e5278803.usrfiles.com/ugd/9ba471_f81ef4e4b5f040038350270590eb2e42.pdf) terms if funded
- [x] I agree to [Provide KYC information](https://9ba4718c-5c73-47c3-a024-4fc4e5278803.usrfiles.com/ugd/9ba471_7d9e73d16b584a61bae92282b208efc4.pdf) if funded above $50,000 USD
- [x] I agree to disclose conflicts of interest
- [x] I agree to adhere to the [Code of Conduct](https://forum.zcashcommunity.com/t/zcg-code-of-conduct/41787) and [Communication Guidelines](https://forum.zcashcommunity.com/t/zcg-communication-guidelines/44284)
- [x] I understand all milestone deliverables will be validated and accepted by their intended users or their representatives, who will confirm that the deliverables meet the required quality, functionality, and usability for each user story.
- [x] I agree that for any new open-source software, I will create a `CONTRIBUTING.md` file that reflects the high standards of Zcash development, using the [`librustzcash` style guides](https://github.com/zcash/librustzcash/blob/main/CONTRIBUTING.md#styleguides) as a primary reference.
- [x] I understand when contributing to existing Zcash code, I am required to adhere to the project specific contribution guidelines, paying close attention to any [merge](https://github.com/zcash/librustzcash/blob/main/CONTRIBUTING.md#merge-workflow), [branch](https://github.com/zcash/librustzcash/blob/main/CONTRIBUTING.md#branch-history), [pull request](https://github.com/zcash/librustzcash/blob/main/CONTRIBUTING.md#pull-request-review), and [commit](https://github.com/zcash/librustzcash/blob/main/CONTRIBUTING.md#commit-messages) guidelines as exemplified in the `librustzcash` repository.
- [x] I agree to post request details on the [Community Forum](https://forum.zcashcommunity.com/c/grants/33)
- [x] I understand it is my responsibility to post a link to this issue on the [Zcash Community Forums](https://forum.zcashcommunity.com/c/grants/33) after this application has been submitted so the community can give input. I understand this is required in order for ZCG to discuss and vote on this grant application.
### Application Owners (@Octocat, @Octocat1)
@Mahmudsudo
### Organization Name
Mahmud Bello
### How did you learn about Zcash Community Grants
zcash forum
### Requested Grant Amount (USD)
30000
### Category
Infrastructure
### Project Lead
```project-lead.yaml
Name: Mahmud Bello
Role: Lead Software Engineer
Background: system software engineering , cryptography , distributed systems and blockchain engineering
Responsibilities: Lead software development , cryptography , software architecture and team management
```
### Additional Team Members
```team-members.yaml
- Name: Olaiya Olayimika
Role: Fullstack engineer / blockchain engineer
Background: blockchain engineering / fullstack development / devops
Responsibilities: smart contract development , full stack development
- Name: Olamide Ganiyu
Role: Frontend engineer / user interface designer
Background: mobile development , frontend development , user interface design and implementation
Responsibilities: ui design and development
```
### Project Summary
**iCert** is a decentralized certificate authority that leverages Zcash's privacy-preserving technology to create a secure, anonymous, and community-governed TLS/SSL certificate management system with token-based voting
### Project Description
### Project Description
iCert is a privacy-preserving, decentralized certificate authority that enables communities to issue, validate, and repudiate TLS/SSL certificates without reliance on centralized CAs. Built to leverage Zcash’s zero-knowledge technology, iCert introduces anonymous, token-based voting and staking to assess certificate health, transparently detect compromise, and coordinate revocation—while safeguarding participant and domain privacy.
- **Problem**: Traditional CAs concentrate power, expose sensitive metadata, and provide limited transparency into validation and revocation decisions. This creates systemic risk, censorship vectors, and privacy leakage.
- **Solution**: A Zcash-integrated CA where certificate issuance, validation, and repudiation are governed by a community of privacy-preserving validators. Votes are staked and recorded using zero-knowledge proofs to preserve anonymity, while aggregated outcomes generate a public, verifiable “certificate health” signal that browsers and services can query.
- **How it works**:
- Domain owner requests a certificates.
- Validators stake tokens and vote (approve/deny/repudiate) using ZK proofs, preserving voter identity and preferences.
- The network produces a privacy-preserving consensus score and revocation status.
- Browsers/services query the certificate plus its consensus state to decide whether to proceed securely.
- **Core features**:
- Privacy-first certificate issuance and lifecycle management
- Anonymous, staked, token-based voting on certificate validity
- Transparent, queryable certificate health and repudiation status
- Incentive mechanisms rewarding honest participation, with slashing for abuse
- **Intended impact**:
- Reduce systemic risks from centralized CAs.
- Enable privacy-preserving issuance and validation for sensitive use cases (e.g., Tor, whistleblowing platforms, activist media).
- Create a reusable blueprint for anonymous governance of shared security infrastructure.
### Proposed Problem
Problem: Traditional CAs concentrate power, expose sensitive metadata, and provide limited transparency into validation and revocation decisions. This creates systemic risk, censorship vectors, and privacy leakage
## Problem Statement
### Current Certificate Authority Issues
- **Privacy Violations**: CAs collect and store sensitive domain information
- **Centralized Control**: Single points of failure and censorship
- **Transparency Gaps**: Limited visibility into certificate validation processes
- **Identity Exposure**: Domain owners must reveal personal information
- **inability to repudiate compromised certificates **
### Proposed Solution
A Zcash-integrated CA where certificate issuance, validation, and repudiation are governed by a community of privacy-preserving validators. Votes are staked and recorded using zero-knowledge proofs to preserve anonymity, while aggregated outcomes generate a public, verifiable “certificate health” signal that browsers and services can query.
How it works:
- Domain owner requests a certificate and pays privately via shielded transactions.
- Validators stake tokens and vote (approve/deny/repudiate) using ZK proofs, preserving voter identity and preferences.
- The network produces a privacy-preserving consensus score and revocation status.
- Browsers/services query the certificate plus its consensus state to decide whether to proceed securely.
### Solution Format
iCert is delivered as a **comprehensive software system** consisting of open-source infrastructure, developer tools, and end-user applications that together create a privacy-preserving decentralized certificate authority.
## Primary Deliverables
### 1. Core Infrastructure Software
#### A. Certificate Authority Server
**Format:** Open-source Rust application
**Components:**
- Domain validation engine (DNS/HTTP challenge automation)
- Certificate issuance pipeline (X.509 generation)
- Zcash payment integration module
- Validator consensus mechanism
- Certificate Transparency log publisher
#### B. Validator Node Software
**Format:** Standalone application package
**Components:**
- Domain verification worker
- Anonymous identity management
- Reputation system client
- Zcash wallet integration
- Consensus participation module
#### C. Governance Platform
**Format:** Web application + smart contracts
**Components:**
- Anonymous voting interface
- Proposal submission system
- Token staking mechanism
- Reputation visualization
- Policy management dashboard
### 2. Developer Tools & SDKs
#### A. Client Libraries
**Languages:** Python, JavaScript/TypeScript, Rust, Go
**Features:**
- Certificate request API
- Zcash payment integration
- Certificate verification
- Revocation checking
#### B. CLI Tool
**Format:** Command-line application
**Capabilities:**
```bash
# Request certificate with private payment
icert request example.com --pay-via-zcash
# Check certificate status
icert status cert-id-12345
# Verify certificate
icert verify example.com
# Manage validator node
icert validator start --config validator.yaml
```
#### C. REST & GraphQL APIs
**Format:** Production-ready API services
**Endpoints:**
- Certificate request/retrieval
- Domain validation status
- Payment verification
- Revocation checking
- Network statistics
### 3. End-User Applications
#### A. Browser Extension
**Platforms:** Chrome, Firefox, Edge, Brave
**Features:**
- Certificate verification overlay
- iCert trust indicator
- Privacy-preserving certificate requests
- One-click domain validation
- Network status dashboard
#### B. Desktop Application
**Platforms:** Windows, macOS, Linux
**Use Cases:**
- Bulk certificate management
- Advanced validator operations
- Portfolio certificate monitoring
- Governance participation
### Dependencies
# iCert Project Dependencies
## Technical Dependencies
### 1. Core Technology Stack
#### Blockchain & Privacy Infrastructure
**Zcash Protocol Integration**
- **Dependencies:**
- `zcash-client-backend` (Rust library)
- `librustzcash` for zero-knowledge proofs
- `zcashd` node software
- Shielded transaction support (Sapling/Orchard)
- **Critical Need:** Stable Zcash RPC API access
**Zero-Knowledge Proof Libraries**
- **Primary:** `bellman` (zk-SNARK library)
- **Alternative:** `halo2` for proof systems
- **Required:** `bls12_381` curve implementation
- **Dependencies:**
- Cryptographic primitives (pairing-friendly curves)
- Proof serialization/deserialization
- Verification libraries
#### Backend Infrastructure
**Programming Languages & Frameworks**
- **Rust:** Core CA server, validator nodes, cryptographic operations
- `tokio` (async runtime)
- `actix-web` or `axum` (web framework)
- `sqlx` (database access)
- `serde` (serialization)
- **Node.js/TypeScript:** Governance platform, APIs
- `express` or `fastify` (web server)
- `ethers.js` or equivalent for blockchain interaction
- `prisma` (database ORM)
**Database Systems**
- **Primary:** PostgreSQL 14+ (certificate storage, metadata)
- **Secondary:** Redis (caching, session management)
- **Optional:** TimescaleDB (time-series monitoring data)
- **Blockchain State:** Dedicated storage for Zcash transaction data
#### Certificate Management
**PKI Infrastructure**
- **OpenSSL 3.0+** or **BoringSSL**
- **X.509 certificate generation libraries**
- `x509-parser` (Rust)
- `node-forge` (JavaScript)
- **ACME Protocol:** RFC 8555 implementation
- **Certificate Transparency:** RFC 6962 log client
#### Frontend Technologies
**Browser Extension**
- Chrome Extension API (Manifest V3)
- Firefox WebExtensions API
- React 18+ or Vue 3
- Web Crypto API
- Storage API (local/sync)
**Web Application**
- Next.js 14+ or similar framework
- React 18+
- Tailwind CSS
- Web3 wallet integration libraries
### Technical Approach
# iCert Technical Approach & Methodology
## Technical Architecture Overview
### System Architecture Diagram
```
┌─────────────────────────────────────────────────────────────┐
│ CLIENT LAYER │
├─────────────┬──────────────┬──────────────┬─────────────────┤
│ Browser │ Desktop │ CLI │ Mobile App │
│ Extension │ Application│ Tool │ (Phase 3) │
└──────┬──────┴──────┬───────┴──────┬───────┴────────┬────────┘
│ │ │ │
└─────────────┴──────────────┴─────────────────┘
│
┌──────────▼──────────┐
│ API GATEWAY │
│ (Load Balanced) │
└──────────┬──────────┘
│
┌─────────────────┼─────────────────┐
│ │ │
┌──────▼─────┐ ┌────────▼────────┐ ┌────▼──────────┐
│CERTIFICATE │ │ GOVERNANCE │ │ VALIDATOR │
│ PALLET │ │ PLATFORM │ │ NETWORK │
└──────┬─────┘ └────────┬────────┘ └────┬──────────┘
│ │ │
│ ┌────────▼────────┐ │
│ │ ZCASH PRIVACY │ │
└────────► LAYER ◄────────┘
└────────┬────────┘
│
┌────────▼────────┐
│ DATA LAYER │
│ PostgreSQL+Redis│
└─────────────────┘
```
## Core Technical Methodologies
### 1. Privacy-Preserving Payment System
#### Zcash Shielded Transaction Integration
**Architecture:**
```rust
// Privacy layer for certificate payments
pub struct PrivatePaymentProcessor {
zcash_client: ZcashClient,
nullifier_store: NullifierDB,
proof_verifier: ZkProofVerifier,
}
impl PrivatePaymentProcessor {
/// Process anonymous certificate payment
pub async fn process_payment(
&self,
certificate_request: CertRequest,
payment_proof: ShieldedPayment,
) -> Result<PaymentVerification> {
// 1. Verify shielded transaction proof
self.verify_shielded_proof(&payment_proof)?;
// 2. Check nullifier hasn't been used (prevent double-spend)
if self.nullifier_store.exists(&payment_proof.nullifier).await? {
return Err(PaymentError::DoubleSpend);
}
// 3. Verify payment amount matches certificate price
self.verify_payment_amount(&payment_proof)?;
// 4. Store nullifier to prevent reuse
self.nullifier_store.insert(&payment_proof.nullifier).await?;
// 5. Issue payment receipt (without revealing payer)
Ok(PaymentVerification {
receipt_id: generate_receipt_id(),
nullifier_commitment: payment_proof.nullifier,
timestamp: Utc::now(),
verified: true,
})
}
/// Verify zero-knowledge proof of payment
fn verify_shielded_proof(
&self,
payment: &ShieldedPayment,
) -> Result<()> {
// Use librustzcash for proof verification
let verification_key = self.get_verification_key();
librustzcash::verify_shielded_payment(
&verification_key,
&payment.proof,
&payment.public_inputs,
)?;
Ok(())
}
}
```
**Technical Components:**
- **Zcash Node Interface:** `zcashd` RPC
- **Proof System:** Sapling/Orchard circuits
- **Storage:** Nullifier database (Redis for fast lookup)
- **Verification:** `librustzcash` binding
**Implementation Steps:**
2. Implement shielded address generation for payments
3. Create payment verification endpoint
4. Build nullifier tracking system
5. Implement receipt generation without identity linkage
### 2. Anonymous Validator Network
#### Validator Identity & Reputation System
**Technical Tools:**
- **VRF Implementation:** `vrf-rs` or custom implementation
- **Randomness Beacon:** Drand or Zcash block hashes
- **Proof System:** Groth16 or PLONK for eligibility proofs
- **Networking:** libp2p for peer-to-peer validator communication
#### Domain Validation Methods
```rust
pub async fn dns_validation(
domain: &str,
expected_token: &str,
) -> Result<bool> {
// Query DNS TXT record for validation token
let resolver = TokioAsyncResolver::tokio(
ResolverConfig::default(),
ResolverOpts::default(),
);
let txt_records = resolver
.txt_lookup(format!("_acme-challenge.{}", domain))
.await?;
for record in txt_records.iter() {
let txt_data = record.to_string();
if txt_data.contains(expected_token) {
return Ok(true);
}
}
Ok(false)
}
```
```rust
pub async fn http_validation(
domain: &str,
token: &str,
) -> Result<bool> {
let url = format!(
"http://{}/.well-known/acme-challenge/{}",
domain, token
);
let client = reqwest::Client::builder()
.timeout(Duration::from_secs(10))
.build()?;
let response = client.get(&url).send().await?;
if response.status().is_success() {
let body = response.text().await?;
return Ok(verify_challenge_response(&body, token));
}
Ok(false)
}
```
**TLS-ALPN-01 Challenge:**
```rust
pub async fn tls_alpn_validation(
domain: &str,
token: &str,
) -> Result<bool> {
// Establish TLS connection with ALPN protocol
let config = ClientConfig::builder()
.with_alpn_protocols(&[b"acme-tls/1"])
.build();
let connector = TlsConnector::from(config);
let stream = TcpStream::connect((domain, 443)).await?;
let tls_stream = connector.connect(domain, stream).await?;
// Verify certificate contains expected token
verify_alpn_certificate(&tls_stream, token)
}
```
### 3. Certificate Issuance Pipeline
#### Certificate Generation System
```rust
pub struct CertificateIssuer {
ca_private_key: RsaPrivateKey,
ca_certificate: X509Certificate,
certificate_db: CertificateDatabase,
ct_log_submitter: CTLogSubmitter,
}
impl CertificateIssuer {
/// Issue certificate after successful validation
pub async fn issue_certificate(
&self,
request: ValidatedCertRequest,
) -> Result<IssuedCertificate> {
// 1. Generate certificate from CSR
let cert_builder = X509Builder::new()?;
// 2. Set standard fields
cert_builder
.set_version(2)?
.set_subject_name(&request.subject)?
.set_issuer_name(self.ca_certificate.subject_name())?
.set_pubkey(&request.public_key)?
.set_not_before(&Asn1Time::days_from_now(0)?)?
.set_not_after(&Asn1Time::days_from_now(90)?)?;
// 3. Add extensions
self.add_standard_extensions(&mut cert_builder, &request)?;
// 4. Sign certificate
cert_builder.sign(&self.ca_private_key, MessageDigest::sha256())?;
let certificate = cert_builder.build();
// 5. Submit to Certificate Transparency logs
let scts = self.ct_log_submitter
.submit_certificate(&certificate)
.await?;
// 6. Store in database (domain is public, requester is private)
self.certificate_db.store(CertificateRecord {
serial_number: certificate.serial_number(),
domain: request.domain.clone(),
certificate: certificate.clone(),
scts: scts.clone(),
issued_at: Utc::now(),
expires_at: Utc::now() + Duration::days(90),
payment_nullifier: request.payment_nullifier,
validator_proofs: request.validation_proofs,
}).await?;
// 7. Return certificate with SCTs
Ok(IssuedCertificate {
certificate,
scts,
receipt: generate_issuance_receipt(),
})
}
fn add_standard_extensions(
&self,
builder: &mut X509Builder,
request: &ValidatedCertRequest,
) -> Result<()> {
// Subject Alternative Names
let mut san = SubjectAlternativeName::new();
for domain in &request.domains {
san.dns(domain);
}
builder.append_extension(san.build(&builder.x509v3_context(None, None))?)?;
// Key Usage
let mut key_usage = KeyUsage::new();
key_usage.digital_signature();
key_usage.key_encipherment();
builder.append_extension(key_usage.build()?)?;
// Extended Key Usage
let mut ext_key_usage = ExtendedKeyUsage::new();
ext_key_usage.server_auth();
ext_key_usage.client_auth();
builder.append_extension(ext_key_usage.build()?)?;
// Authority Key Identifier
let auth_key_id = AuthorityKeyIdentifier::new()
.keyid(true)
.build(&builder.x509v3_context(Some(&self.ca_certificate), None))?;
builder.append_extension(auth_key_id)?;
Ok(())
}
}
```
**Certificate Transparency Integration:**
```rust
pub struct CTLogSubmitter {
log_servers: Vec<CTLogServer>,
http_client: reqwest::Client,
}
impl CTLogSubmitter {
/// Submit certificate to multiple CT logs
pub async fn submit_certificate(
&self,
certificate: &X509Certificate,
) -> Result<Vec<SignedCertificateTimestamp>> {
let mut scts = Vec::new();
// Submit to at least 2 logs (required for browser acceptance)
for log_server in &self.log_servers {
match self.submit_to_log(log_server, certificate).await {
Ok(sct) => scts.push(sct),
Err(e) => eprintln!("Failed to submit to {}: {}", log_server.url, e),
}
if scts.len() >= 2 {
break;
}
}
if scts.len() < 2 {
return Err(CTError::InsufficientSCTs);
}
Ok(scts)
}
async fn submit_to_log(
&self,
log_server: &CTLogServer,
certificate: &X509Certificate,
) -> Result<SignedCertificateTimestamp> {
let cert_der = certificate.to_der()?;
let chain_der = self.get_issuer_chain_der()?;
let request_body = json!({
"chain": [
base64::encode(&cert_der),
base64::encode(&chain_der),
]
});
let response = self.http_client
.post(&format!("{}/ct/v1/add-chain", log_server.url))
.json(&request_body)
.send()
.await?;
let sct_response: CTLogResponse = response.json().await?;
Ok(SignedCertificateTimestamp {
version: sct_response.sct_version,
log_id: log_server.log_id.clone(),
timestamp: sct_response.timestamp,
signature: sct_response.signature,
})
}
}
```
### 4. Anonymous Governance System
#### Token-Based Voting with Privacy
```rust
pub struct GovernanceSystem {
proposals: ProposalStore,
vote_aggregator: PrivateVoteAggregator,
token_verifier: StakeVerifier,
}
impl GovernanceSystem {
/// Submit anonymous vote on proposal
pub async fn submit_vote(
&self,
vote: PrivateVote,
) -> Result<VoteReceipt> {
// 1. Verify voter has sufficient stake (without revealing amount)
self.token_verifier.verify_stake_proof(&vote.stake_proof)?;
// 2. Check nullifier hasn't voted on this proposal
if self.has_voted(&vote.proposal_id, &vote.voter_nullifier).await? {
return Err(GovernanceError::AlreadyVoted);
}
// 3. Verify ZK proof of valid vote
self.verify_vote_proof(&vote)?;
// 4. Record vote commitment (not the actual vote)
self.vote_aggregator.record_vote(
&vote.proposal_id,
&vote.vote_commitment,
&vote.voter_nullifier,
).await?;
Ok(VoteReceipt {
proposal_id: vote.proposal_id,
nullifier: vote.voter_nullifier,
recorded_at: Utc::now(),
})
}
/// Reveal voting results without revealing individual votes
pub async fn tally_votes(
&self,
proposal_id: &[u8; 32],
) -> Result<VotingResult> {
let votes = self.vote_aggregator
.get_votes(proposal_id)
.await?;
// Homomorphic aggregation of encrypted votes
let aggregated_result = self.aggregate_votes_privately(votes)?;
// Generate proof that tallying was correct
let tally_proof = self.generate_tally_proof(
proposal_id,
&aggregated_result,
)?;
Ok(VotingResult {
proposal_id: *proposal_id,
yes_votes: aggregated_result.yes_count,
no_votes: aggregated_result.no_count,
abstain_votes: aggregated_result.abstain_count,
total_stake_weight: aggregated_result.total_stake,
tally_proof,
})
}
}
```
**Vote Encryption Schema:**
```rust
pub struct PrivateVote {
pub proposal_id: [u8; 32],
pub vote_commitment: [u8; 32], // Commitment to vote choice
pub stake_proof: ZkProofOfStake, // Proof of stake (amount private)
pub voter_nullifier: [u8; 32], // Unique voter ID for this proposal
pub zk_proof: VoteValidityProof, // Proof vote is well-formed
}
impl PrivateVote {
pub fn create(
proposal_id: [u8; 32],
vote_choice: VoteChoice,
stake_amount: u64,
voter_secret: &VoterSecret,
) -> Result<Self> {
// Create commitment to vote
let vote_commitment = pedersen_commit(
&vote_choice.to_bytes(),
&voter_secret.randomness,
);
// Generate nullifier (unique per proposal, not linkable across proposals)
let voter_nullifier = generate_nullifier(
&proposal_id,
&voter_secret.key,
);
// Prove stake without revealing amount
let stake_proof = generate_stake_proof(
stake_amount,
MIN_STAKE_REQUIREMENT,
&voter_secret.stake_secret,
)?;
// Prove vote is well-formed
let zk_proof = generate_vote_validity_proof(
&vote_choice,
&vote_commitment,
&voter_nullifier,
&stake_proof,
)?;
Ok(PrivateVote {
proposal_id,
vote_commitment,
stake_proof,
voter_nullifier,
zk_proof,
})
}
}
```
### 5. Reputation System Architecture
#### Privacy-Preserving Reputation Tracking
```rust
pub struct ReputationEngine {
commitments: CommitmentStore,
proof_verifier: ZkProofVerifier,
reputation_threshold: u64,
}
impl ReputationEngine {
/// Update validator reputation without revealing score
pub async fn update_reputation(
&self,
validator: &ValidatorCommitment,
performance: ValidationPerformance,
) -> Result<ReputationUpdate> {
// 1. Validator submits ZK proof of current reputation
let current_rep_proof = validator.generate_reputation_proof()?;
self.proof_verifier.verify(¤t_rep_proof)?;
// 2. Calculate new reputation (server-side, private)
let reputation_delta = self.calculate_reputation_change(&performance);
let new_reputation = current_rep_proof.reputation_value + reputation_delta;
// 3. Generate new commitment to updated reputation
let new_commitment = pedersen_commit(
&new_reputation.to_le_bytes(),
&generate_random(),
);
// 4. Store commitment (not actual value)
self.commitments.update(
&validator.commitment,
new_commitment,
).await?;
// 5. Return proof of update for validator
Ok(ReputationUpdate {
old_commitment: validator.commitment,
new_commitment,
update_proof: self.generate_update_proof(
¤t_rep_proof,
reputation_delta,
&new_commitment,
)?,
})
}
/// Verify validator meets reputation threshold without revealing score
pub fn verify_reputation_threshold(
&self,
proof: &ReputationProof,
) -> Result<bool> {
// Verify ZK proof that: reputation >= threshold
// Without learning: actual reputation value
let public_inputs = vec![
self.reputation_threshold,
proof.commitment,
];
verify_zk_proof(
&REPUTATION_VERIFICATION_KEY,
&proof.proof,
&public_inputs,
)
}
}
```
**Reputation Circuit:**
```rust
/// Zero-knowledge circuit for reputation proofs
pub struct ReputationCircuit {
// Private inputs
reputation_value: u64,
reputation_randomness: [u8; 32],
// Public inputs
reputation_threshold: u64,
reputation_commitment: [u8; 32],
}
impl Circuit for ReputationCircuit {
fn synthesize<CS: ConstraintSystem>(
self,
cs: &mut CS,
) -> Result<(), SynthesisError> {
// 1. Allocate private reputation value
let rep_value = cs.alloc(|| "reputation", || {
Ok(Fr::from(self.reputation_value))
})?;
// 2. Verify commitment is correct
let computed_commitment = pedersen_commit_circuit(
cs,
&rep_value,
&self.reputation_randomness,
)?;
cs.enforce(|| "commitment matches",
|lc| lc + computed_commitment,
|lc| lc + CS::one(),
|lc| lc + self.reputation_commitment,
);
// 3. Prove reputation >= threshold
let threshold = cs.alloc_input(|| "threshold", || {
Ok(Fr::from(self.reputation_threshold))
})?;
// reputation - threshold should be non-negative
let difference = sub_circuit(cs, rep_value, threshold)?;
enforce_non_negative(cs, difference)?;
Ok(())
}
}
```
## Development Tools & Frameworks
### 1. Programming Languages
**Rust (Primary Backend)**
- **Version:** 1.75+ (latest stable)
- **Use Cases:** CA server, validators, cryptography
- **Key Libraries:**
- `tokio` - Async runtime
-`axum` - Web framework
- `sqlx` - Database access
- `openssl` / `rustls` - TLS/PKI
- `bellman` / `halo2` - ZK proofs
- `librustzcash` - Zcash integration
**TypeScript/JavaScript**
- **Version:** Node.js 20 LTS
- **Use Cases:** Governance platform, APIs, browser extension
- **Key Libraries:**
- `express` / `fastify` - API server
- `react` 18+ - Frontend
- `ethers.js` - Blockchain interaction
- `prisma` - ORM
### 2. Cryptographic Tools
**Zero-Knowledge Proof Systems**
```toml
[dependencies]
bellman = "0.14" # Groth16 proofs
halo2_proofs = "0.3" # PLONK-based proofs
arkworks-rs = "0.4" # Cryptographic primitives
```
**Zcash Integration**
```toml
[dependencies]
zcash_client_backend = "0.10"
zcash_primitives = "0.13"
zcash_proofs = "0.13"
librustzcash = "0.2"
```
**PKI & Certificates**
```toml
[dependencies]
openssl = "0.10"
x509-parser = "0.15"
rcgen = "0.11" # Certificate generation
rustls = "0.21" # TLS implementation
```
### 3. Database & Storage
**PostgreSQL Configuration**
```sql
-- Certificate storage schema
CREATE TABLE certificates (
id SERIAL PRIMARY KEY,
serial_number BYTEA UNIQUE NOT NULL,
domain VARCHAR(255) NOT NULL,
certificate BYTEA NOT NULL,
issued_at TIMESTAMP NOT NULL,
expires_at TIMESTAMP NOT NULL,
payment_nullifier BYTEA UNIQUE NOT NULL,
revoked BOOLEAN DEFAULT FALSE,
revocation_reason VARCHAR(100),
INDEX idx_domain (domain),
INDEX idx_serial (serial_number),
INDEX idx_expires (expires_at)
);
-- Nullifier tracking (prevent double-spend)
CREATE TABLE nullifiers (
nullifier BYTEA PRIMARY KEY,
used_at TIMESTAMP NOT NULL,
context VARCHAR(50) NOT NULL -- 'payment', 'vote', etc.
);
-- Validator commitments (anonymous identities)
CREATE TABLE validators (
commitment BYTEA PRIMARY KEY,
reputation_commitment BYTEA NOT NULL,
stake_proof BYTEA NOT NULL,
registered_at TIMESTAMP NOT NULL,
last_validation TIMESTAMP,
validation_count INTEGER DEFAULT 0
);
-- Governance proposals and votes
CREATE TABLE proposals (
id BYTEA PRIMARY KEY,
title VARCHAR(255) NOT NULL,
description TEXT NOT NULL,
created_at TIMESTAMP NOT NULL,
voting_ends_at TIMESTAMP NOT NULL,
status VARCHAR(20) NOT NULL
);
CREATE TABLE vote_commitments (
proposal_id BYTEA REFERENCES proposals(id),
voter_nullifier BYTEA NOT NULL,
vote_commitment BYTEA NOT NULL,
stake_proof BYTEA NOT NULL,
submitted_at TIMESTAMP NOT NULL,
PRIMARY KEY (proposal_id, voter_nullifier)
);
```
**Redis Configuration**
```redis
# Caching layer
SET certificate:example.com:latest <cert_data> EX 3600
SET nullifier:check:<nullifier_hash> 1 EX 7776000 # 90 days
# Rate limiting
INCR rate:ip:<ip_address>:requests EX 3600
INCR rate:domain:<domain>:validations EX 86400
# Validator selection pool
ZADD validator:eligible <reputation_score> <validator_commitment>
```
### 4. API Framework
**REST API Structure**
```rust
use actix_web::{web, App, HttpServer, HttpResponse};
#[actix_web::main]
async fn main() -> std::io::Result<()> {
HttpServer::new(|| {
App::new()
// Certificate endpoints
.route("/api/v1/certificates/request",
web::post().to(request_certificate))
.route("/api/v1/certificates/{serial}",
web::get().to(get_certificate))
.route("/api/v1/certificates/{serial}/revoke",
web::post().to(revoke_certificate))
// Payment endpoints
.route("/api/v1/payments/verify",
web::post().to(verify_payment))
.route("/api/v1/payments/address",
web::get().to(get_payment_address))
// Validator endpoints
.route("/api/v1/validators/register",
web::post().to(register_validator))
.route("/api/v1/validators/validate",
web::post().to(submit_validation))
// Governance endpoints
.route("/api/v1/governance/proposals",
web::get().to(list_proposals))
.route("/api/v1/governance/vote",
web::post().to(submit_vote))
.route("/api/v1/governance/results/{proposal_id}",
web::get().to(get_results))
})
.bind("
### Upstream Merge Opportunities
None
### Hardware/Software Costs (USD)
15000
### Hardware/Software Justification
Hosting , deployment and tokenization
### Service Costs (USD)
0
### Service Costs Justification
none
### Compensation Costs (USD)
15000
### Compensation Costs Justification
Backend Engineer - 5000
Cryptography / blockchain Engineer - 5000
Frontend Engineer - 4000
### Total Budget (USD)
30000
### Previous Funding
No
### Previous Funding Details
_No response_
### Other Funding Sources
No
### Other Funding Sources Details
_No response_
### Implementation Risks
Implementation Risks
Technical Complexity Challenges
Zero-Knowledge Proof Performance: Generating and verifying ZK proofs for every certificate validation could create significant computational overhead, potentially slowing down certificate issuance and verification processes
Zcash Integration Complexity: Building robust cross-chain bridges while maintaining privacy guarantees is technically demanding and may face unexpected integration issues
Scalability Constraints: Privacy-preserving operations are computationally intensive, which could limit the number of certificates the system can process compared to traditional CAs
Adoption Barriers
Browser Compatibility: Major browsers (Chrome, Firefox, Safari) would need to integrate support for this decentralized CA system, which faces significant regulatory and technical hurdles
Trust Bootstrap Problem: Without established reputation, convincing users and organizations to trust certificates from a new, anonymous CA system will be extremely difficult
Developer Learning Curve: The complexity of privacy-preserving cryptography and Zcash integration may deter developers from adopting the platform
Economic Viability Risks
Token Volatility: Dependence on ZEC-based tokens exposes the system to cryptocurrency price volatility, potentially making certificate costs unpredictable
Insufficient Voting Participation: If not enough token holders participate in anonymous voting, the governance system could fail to achieve meaningful consensus
Free-Rider Problem: Users may benefit from the system without contributing to governance, undermining the token economics
Security Vulnerabilities
Novel Attack Vectors: Privacy-preserving systems introduce unique attack surfaces that may not be well-understood initially
Sybil Attacks: Despite privacy features, malicious actors could potentially create multiple anonymous identities to manipulate voting
Key Management: Users managing private keys for anonymous voting and certificate access adds complexity and risk of loss
Regulatory Challenges
Legal Compliance: Anonymous certificate issuance may conflict with regulations requiring CA accountability and auditability
KYC/AML Requirements: Privacy-first approach may face regulatory pushback in jurisdictions requiring identity verification
Liability Questions: Unclear legal responsibility when certificate misuse occurs through an anonymous system
Potential Side Effects
Unintended Negative Consequences
Facilitation of Malicious Activities
Criminal Use Cases: Complete anonymity could enable certificates for phishing sites, malware distribution, or illegal content hosting without accountability
Abuse Without Recourse: The privacy features that protect legitimate users also protect bad actors, making it difficult to revoke certificates for malicious sites
Law Enforcement Friction: Anonymous certificate issuance could hinder legitimate investigations and create tensions with authorities
Privacy Paradoxes
Reduced Transparency: While privacy is the goal, the lack of transparency could actually reduce trust among users who want to verify certificate legitimacy
Metadata Leakage: Despite privacy features, timing attacks, network analysis, or voting patterns could potentially deanonymize participants over time
Privacy Fatigue: The complexity of maintaining privacy through ZK proofs and shielded transactions could overwhelm average users
Economic Distortions
Wealth Concentration: Token-based voting could lead to governance capture by large token holders, creating a plutocracy rather than true decentralization
Speculation Over Utility: The token might be treated as a speculative asset rather than a governance tool, distorting intended economic incentives
Market Manipulation: Anonymous voting could be exploited for market manipulation without accountability
Technical Debt and Fragmentation
Maintenance Burden: Complex privacy-preserving cryptography requires ongoing maintenance and updates as vulnerabilities are discovered
Ecosystem Fragmentation: Creating an alternative CA system could fragment the web security ecosystem, potentially weakening overall security
Resource Intensive: High computational requirements for ZK proofs could exclude users with limited resources, creating inequality
Social and Ethical Impacts
Trust Erosion: If high-profile abuse cases occur, it could damage trust in privacy-preserving technologies more broadly
Regulatory Backlash: Negative incidents could trigger aggressive regulation that harms legitimate privacy tools
False Sense of Security: Users might overestimate their privacy guarantees and take unnecessary risks
Mitigation Considerations
While these risks and side effects are significant, the document doesn't provide detailed mitigation strategies for most of them. Successful implementation would require:
Robust governance mechanisms to address malicious use without compromising privacy
Clear policies for certificate revocation that balance privacy with security
Regulatory engagement to establish compliant privacy-preserving frameworks
Comprehensive security audits before mainnet deployment
User education about privacy limitations and proper usage
Economic safeguards against governance capture and token volatility
The tension between absolute privacy and accountability represents the core challenge that could determine whether iCert succeeds or fails in practice.Retry[Claude can make mistakes. Please double-check responses.](https://support.anthropic.com/en/articles/8525154-claude-is-providing-incorrect-or-misleading-responses-what-s-going-on)
### Potential Side Effects
Facilitation of Malicious Activities
Criminal Use Cases: Complete anonymity could enable certificates for phishing sites, malware distribution, or illegal content hosting without accountability
Abuse Without Recourse: The privacy features that protect legitimate users also protect bad actors, making it difficult to revoke certificates for malicious sites
### Success Metrics
Success Metrics
Anonymous certificates issued
Private voting participation rates
Zero-knowledge proof efficiency
Zcash privacy feature utilization
### Startup Funding (USD)
10000
### Startup Funding Justification
initial development costs
### Milestone Details
```milestones.yaml
- Milestone: 1
Amount (USD): 10000
Expected Completion Date: 4 weeks from start
User Stories:
- "As a developer, I want to integrate Zcash shielded transactions into the system, so that all token transfers remain private"
- "As a certificate validator, I want to verify certificate validity without seeing domain details, so that privacy is maintained"
- "As a token holder, I want to vote on certificate validity anonymously, so that my voting choices cannot be traced back to me"
- "As a domain owner, I want to request SSL certificates without exposing my identity, so that my privacy is protected"
Deliverables:
- Zcash SDK integration with support for shielded transactions (Sapling/Orchard protocols)
- Zero-knowledge proof system for certificate validation with commitment and nullifier implementation
- Anonymous voting mechanism with private vote commitments and ZK proofs
- Privacy-preserving certificate issuance system with encrypted metadata storage
- Basic certificate pallet supporting lifecycle management (issuance, renewal, revocation)
- Test suite demonstrating all core privacy features
Acceptance Criteria: Successfully execute shielded ZEC transactions, generate and verify zero-knowledge proofs for certificates in under 5 seconds, enable anonymous voting with untraceable votes, and issue certificates without revealing domain owner identities
- Milestone: 2
Amount (USD): 10000
Duration: 4 weeks
User Stories:
- "As a voter, I want to build reputation through participation without exposing my voting history, so that I maintain privacy while gaining trust"
- "As a multi-chain user, I want to use certificates across different networks while maintaining privacy, so that my cross-chain activity remains confidential"
- "As a power user, I want optimized ZK proofs that generate quickly, so that I can use the system efficiently"
- "As a governance participant, I want an intuitive interface to vote anonymously, so that I can participate without technical barriers"
Deliverables:
- Confidential reputation scoring system using cryptographic commitments
- Privacy-preserving cross-chain bridge for Ethereum and Polkadot with ZK proof relay
- Optimized zero-knowledge proof circuits with batch processing and compression
- Web-based anonymous governance interface with voting dashboard
- Private certificate request UI with wallet integration
- Mobile-friendly verification implementation
Acceptance Criteria: Users can accumulate verifiable reputation privately, certificates work across multiple chains with maintained privacy, ZK proof generation time reduced by 50% with mobile device support, and non-technical users can participate through intuitive interfaces
- Milestone: 3
Amount (USD): 10000
Duration: 4 weeks
User Stories:
- "As a security researcher, I want confidence that the system has no privacy vulnerabilities, so that I can trust it with sensitive operations"
- "As a Zcash user, I want to use the certificate system on mainnet with real ZEC, so that I can obtain production certificates"
- "As a developer, I want comprehensive documentation and SDKs, so that I can integrate privacy-preserving certificates into my application"
- "As an early adopter, I want to be part of the community launch, so that I can help establish the privacy-preserving certificate ecosystem"
Deliverables:
- Third-party security audit with privacy analysis and vulnerability remediation
- Zcash mainnet deployment with production smart contracts and monitoring dashboard
- Complete API documentation and SDK libraries (Rust, JavaScript, Python)
- Integration tutorials, example applications, and video guides
- Community launch campaign with partnerships
- Initial certificate issuance to pilot users and governance establishment
- Public metrics dashboard for adoption and privacy metrics
Acceptance Criteria: Security audit completed with all critical issues resolved and privacy guarantees verified, system stable on Zcash mainnet for production use, developers can integrate using documentation alone, 100+ certificates issued to real users, and active community governance with at least 5 privacy-focused project partnerships
```
### Supporting Documents
```files.yaml
```
Introducing iCert: Certificate Authority for the Decentralized Web
The Problem We’re Solving
Our Privacy-First Solution
Certificate Issuance
Privacy-Preserving Governance
**Transparent Yet Private**
How It Works
Why This Matters for Zcash
What We’re Building
Community Involvement
Impact for Privacy-Conscious Users
Let’s Discuss!