Cloak

Cloak Privacy Corp builds private financial infrastructure on Solana, letting users and enterprises conduct shielded transfers, swaps, and treasury operations whose amounts and counterparties are hidden from public explorers — while keeping a compliance pathway open through cryptographic viewing keys.

The Problem: Every Solana Transaction Is Public

Solana's ledger is fully transparent by design. Every transfer, swap, and treasury movement is permanently indexed and readable by anyone — competitors, front-runners, or data aggregators. For individual users this is a nuisance; for crypto-native businesses, payroll operators, and treasuries, it creates a real operational risk. The standard workaround — routing sensitive flows through a centralized exchange — sacrifices the security guarantees of self-custody and on-chain settlement. Cloak is built to close that gap natively on Solana.

How It Works

Cloak's core is a shielded UTXO (Unspent Transaction Output) pool running as a Solana on-chain program (Program ID: zh1eLd6rSphLejbFfJEneUwzHRfMKxgzrgkfwA6qRkW). The UTXO model — familiar from privacy-focused chains such as Zcash — is adapted here for Solana's account-based runtime. Each shielded operation follows a 2-in/2-out transaction structure, and a nullifier system prevents double-spending of committed values without revealing the notes themselves. Merkle tree commitments are recorded on-chain so anyone can verify the integrity of the pool, but the underlying amounts, sender addresses, and recipient addresses remain hidden.

Zero-knowledge proofs carry the cryptographic load. Cloak uses Groth16 proofs, which are compact and fast to verify. Browser-native proof generation completes in under three seconds; on-chain verification takes under 50 milliseconds. This puts the computational cost inside the client — there is no centralized prover that users must trust.

The system is structured around three components:

• SDK (@cloak.dev/sdk) — TypeScript library handling proof generation, transaction building, and account scanning. Developers integrate privacy into any dApp or wallet without managing circuits, Merkle trees, or prover infrastructure directly.
• Shield Pool Program — the on-chain Solana program that verifies proofs and manages state transitions for deposits, transfers, withdrawals, and swaps.
• Circuit Package — generates Groth16 artifacts and exports verifier keys for the cryptographic backend.

All transaction flows except deposits require cryptographic signatures from either a browser wallet or a server keypair, maintaining clear sender attribution at the protocol level.

Features and Use Cases

Cloak's initial mainnet alpha supports three core operations:

Private transfers — Send SOL, USDC, or USDT with amounts and addresses hidden from the public ledger. The minimum deposit to enter the shielded pool is 0.01 SOL; shielding is free. Withdrawing back to a standard Solana account incurs a 0.3% fee. Users pay no gas on transfers made within the shielded pool.

Shielded swaps — Exchange tokens inside the privacy pool without exposing trade sizes or routing to MEV bots or on-chain watchers.

Batch payments and treasury management — Payroll operators and DeFi treasuries can move funds in bulk without telegraphing strategy or counterparty relationships to the market.

Compliance through viewing keys — Privacy does not mean unaccountability. Each shielded account has an associated viewing key, derived from the user's wallet signature, that can be shared with an auditor, regulator, or internal compliance team. The viewing key reveals the full transaction history of that account to its recipient while revealing nothing to the public. Cloak also supports encrypted chain notes and controlled compliance workflows for more structured audit trails.

The product is available as a web application, a mobile Android app (published on Google Play), and a TypeScript SDK for protocol integrations.

Token Support

Cloak currently supports three assets in its shielded pool: SOL, USDC, and USDT. The SDK is designed to work with any SPL token, so broader coverage is a natural extension as the product matures.

No native governance or protocol token has been announced.

Team

Cloak is a Brazil-based team with backgrounds in Solana infrastructure and traditional finance:

• Arthur Bretas (CEO) — Previously an SVM engineer at SonicSVM, a Solana Virtual Machine implementation.
• Marcelo Feitoza (CTO) — Founding engineer at Compute Labs.
• Matheus Macedo (COO) — Former software engineer at BTG Pactual, Brazil's largest investment bank.
• Victor Carvalho (CFO) — Former software engineer at BTG Pactual.

The BTG Pactual background is notable for a privacy product targeting institutional and enterprise users — it suggests familiarity with compliance requirements and institutional financial workflows.

Funding and Backing

Cloak raised a $250,000 pre-seed through the Colosseum Accelerator, the program associated with Colosseum's Solana hackathon series. The cohort 4 acceptance rate was approximately 0.67% of combined submissions. Additional backers include Turbin3, Blueshift, and Superteam Brasil — all Solana ecosystem organizations with development and talent networks.

Three protocols have integrated Cloak in production: PagFinance, Nora Finance, and Samui. Additional listed partners include 4Pay, Surf Cash, and Range.

Security and Audit Status

Cloak's mainnet deployment is currently in alpha. As of mid-2026, no completed public security audit for the current protocol version has been announced. Users should treat the alpha label seriously — the shielded pool program and ZK circuits have not been publicly reviewed by a named auditor. Cloak publishes its verifier keys and on-chain program ID, enabling independent verification of the cryptographic setup, but a formal audit of the full codebase remains an open item for the project.

Solana Fit

Cloak is built natively for Solana rather than adapted from an EVM-chain architecture. The choice of Groth16 proofs over heavier SNARK schemes, and browser-native proof generation under three seconds, reflects a deliberate tradeoff toward Solana's UX expectations: fast finality and low fees. The on-chain Shield Pool program settles on Solana's runtime directly, and the SDK integrates with standard Solana wallet adapters.

As Solana's Confidential Balances extension (a native ZK-encrypted SPL token standard) moves toward wider deployment, Cloak occupies a complementary position: it addresses existing plain SPL tokens without waiting for protocol-level privacy, and its viewing-key compliance model aligns with the selective-disclosure approach embedded in Confidential Balances.

Current Status

Cloak is live on Solana mainnet in alpha. Private USDC, USDT, and SOL payments are operational, and the team indicated a broader public rollout is in progress. The Twitter account (@cloak_xyz) and documentation at docs.cloak.ag are active. Given the alpha label and lack of a completed public audit, the project is in early live deployment rather than a production-hardened state.