GRAYBOX

MORA x @cloak_ag x GrayBox. @siriuslabshq solutions.

Every Solana payment leaks more than value. It leaks the receiver. It leaks the funding path. It leaks the operational graph around a transaction. We built a three-layer payment privacy stack to reduce those leaks, without modifying Cloak’s on-chain program. Here’s how it works 🧵

We built ''Our GrayBox Solution × Cloak'' for your side track in @colosseum frontier. ECDH stealth addresses on top of Cloak's shielded pool. Recipient identity hidden, amount hidden, only a ZK proof on-chain. Real mainnet TX executed, live deployment running. Would love to explore a collaboration, happy to walk you through the integration. We at @siriuslabshq want to collaborate. In 2008, Satoshi described something: a trustless, peer-to-peer electronic payment system with no intermediaries. What we've built so far is the foundation, GrayBox hides the recipient, Cloak hides the amount. But this is only the beginning. The natural next step is bringing MORA into the stack. MORA handles offline payment authorization, Alice locks SOL once, signs vouchers offline, Bob settles later. When that settlement goes through Cloak's shielded pool, the result is complete privacy: who paid is hidden, who received is hidden, how much is hidden, and when it happened is unlinkable. No other stack on Solana closes all four gaps simultaneously. For Cloak, this means a concrete institutional use case: a merchant or remittance operator who needs offline capability AND full settlement privacy. That's a market Cloak doesn't reach today without MORA. For @siriuslabshq , Cloak provides the shielded settlement layer we'd otherwise have to build ourselves. The integration is already started. The architecture is proven. What we're proposing is a formal collaboration to take it to mainnet together, joint documentation, co-marketing, and a shared target: the first fully private, fully offline payment stack on Solana. This is a win for both sides. And it closes a gap neither of us closes alone.

🚨 Last call to submit for the Cloak Track You currently have a 10% chance of winning one of the prizes. There are only 14 hours left before submissions close. If you’ve been building, this is the moment to ship. Submit here: superteam.fun/earn/listing/c…

We took this vision seriously. GrayBox + Cloak closes both gaps at once: Cloak hides the amount, GrayBox hides the recipient. Neither layer alone is enough together they're the complete institutional privacy stack Solana was missing. We took this vision seriously. GrayBox + @cloak_ag closes both gaps at once. Cloak hides how much was transferred, Groth16 shielded pool, amount never visible on-chain. GrayBox hides who received it, ECDH stealth addresses, recipient identity never on-chain. GrayBox hides who received it, ECDH stealth addresses, recipient identity never on-chain. Neither layer alone is enough. Remove Cloak and the amount is public. Remove GrayBox and the recipient is public. Together: only a ZK proof on-chain. Nothing else. This is what institutional payment privacy looks like when you build it properly, not as a feature, but as the foundation. @siriuslabshq

Here’s @toly himself talking about privacy. The interesting part is that if you take the core ideas from this speech and assemble them into a single solution, you basically end up with Cloak. From day one, we didn’t just build to solve privacy onchain. We built to solve the problems inside existing privacy solutions too. Most privacy infrastructure today was designed mainly for consumers, while probably missing the most important users: companies and institutions. Cloak was built for them. Native compliance. Seamless integration. Institutional-grade infrastructure. We’re building the infrastructure for the money already moving onchain today, and for the trillions coming in the next few years. It's the privacy season, it's Cloak season.

Every Solana payment leaks two things: who received and how much. We closed both. GrayBox hides the recipient, ECDH stealth addresses. Cloak hides the amount, Groth16 ZK proof. One ZK proof on-chain. Nothing else visible. GrayBox built by @siriuslabshq Live deployment + real mainnet TX 👇 …aybox-cloak-production.up.railway.app

GrayBox generates a one-time ECDH stealth address per payment so the recipient's identity is never on-chain, and Cloak routes the settlement through a Groth16 shielded pool so the amount is never on-chain together, only a ZK proof is visible on-chain, nothing else. github.com/sirius-labs-de…

The Cloak track is live at @colosseum Frontier. We're funding products that only exist because privacy makes them possible. Let's build: superteam.fun/earn/listing/c…

We just submitted Sirius Labs to @colosseum Frontier 2026. Every Solana payment leaks three things: the signing key goes online, connectivity is required, and settlement leaves a public trail. We built the stack that closes all three.

Solution: GRAYBOX

A mixer is not privacy. An open validator set is not neutrality. The contract runs on a machine you will never see, controlled by people you will never name. Privacy is Normal. Because there are GRAYBOX solutions in @solana.

We take your privacy seriously, we don't know about you.

User control, enforced by proof.

A while ago we asked a simple question: Why does using Solana mean exposing your entire financial life to the world? GrayBox is the answer. Selective, verifiable privacy. Privacy by default. Verifiability when needed. The primitive that scales privacy to institutions.

Why GrayBox is built natively on Solana, not as a sidechain or rollup: Latency: Privacy steps happen within standard block times. No rollup settlement wait. Throughput: Lightweight cryptographic checks. Mass adoption without clogging the chain. Composability: Integrates with existing Solana DeFi. Doesn't isolate liquidity. Privacy should be frictionless. On Solana, it can be.

Your Solana wallet: — Public diary — Trading strategy, readable by anyone — Net worth announcement — Target for front-runners GrayBox: Yours.

GrayBox is ZK-compatible. Not ZK-dependent. Here's why that matters 1/ ZK proofs are powerful but add complexity and compute cost. Requiring them for every operation limits adoption. 2/ GrayBox works without ZK proofs. Stealth addresses + vault isolation + relayers = strong privacy by default. 3/ ZK layers can be added modularly for: — Private balance proofs — Anonymous transfers — Compliance proofs (Proof of Non-Association) — DAO voting privacy 4/ Usable privacy now. Institutional-grade ZK proofs when you need them.

Every on-chain action you take is permanent. Your competitors analyze your history. Front-runners predict your next move. Wallets get targeted because their balance is public. This isn't a bug in Solana. It's the design. GrayBox is the layer that fixes it.

Institutions don't need full anonymity. They need controlled transparency. GrayBox is the first privacy primitive that actually understands this distinction. Privacy by default. Disclosure by choice.

View Keys, the institutional unlock GrayBox users can share a View Key with: — Tax authorities — Auditors — Compliance teams This reveals specific transaction history to the recipient. The rest of the world sees nothing. Transparency is opt-in and targeted. Not default and broadcast. This is how institutional DeFi becomes real.

Hot take: Privacy pools are not the answer. They still rely on shared anonymity sets. One bad actor in the set? Complex exclusion proofs required. Regulators don't accept them. You can't solve the tainted pool problem by making the pool slightly smarter. You have to eliminate the pool entirely.